What does the rendering engine do when it encounters JavaScript?$?

Switches to Javascript Interpreter

Which of the following is a read-only property?$?

PerformanceTiming.navigationStart

PerformanceTiming.navigationStart & PerformanceTiming.fetchStart

Which of the following property is associated with the Response event?$?

both responseStart and responseEnd

Why do we need to use an onload event in the script tag after using the async attribute?$?

Invoke code during page loading

Invoke code during script loading

Why do we need to use an onload event in the script tag after using the async attribute??

Invoke code during page loading

Invoke code during script loading

What is the purpose of holding whatever tag you create in the attribute type?

To identify the scripting language

Which of the following does JSON.stringify not serialize?

Both Undefined values and Functions within an object

What is the purpose of the timing property in the window.performance object?

Time of navigation and page load event

What does it indicate when the type attribute of the navigation object is set to 2?

Navigation by moving back through history

Navigation by moving forward through history

Navigation by moving back & forward through history

133 + Mcqs in Invocation And Performance Navigation in Javascript Page 3 McqOptions

101.	How many properties are there in the interface PerformanceTiming?$?
A.	21
B.	22
C.	23
D.	24
Answer» B. 22

Discussion

102.	What can be done to monitor the memory usage?$?
A.	Profiling
B.	Sequencing
C.	Serializing
D.	None of the mentioned
Answer» B. Sequencing

Discussion

103.	What does the rendering engine do when it encounters JavaScript?$?
A.	Skips the code
B.	Continues painting
C.	Switches to Javascript Interpreter
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

104.	Which of the following is a read-only property?$?
A.	PerformanceTiming.navigationStart
B.	PerformanceTiming.fetchStart
C.	PerformanceTiming.navigationStart & PerformanceTiming.fetchStart
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

105.	What is the function of the memory object?$?
A.	Gets unused memory details
B.	Shows optimization
C.	Gets memory usage
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

106.	What does the constant TYPE_BACK_FORWRD indicate?$?
A.	Navigation via browser history
B.	Navigation via user request
C.	Navigation via URL
D.	None of the mentioned
Answer» B. Navigation via user request

Discussion

107.	What are the parameters of the attachEvent function?$?
A.	Function
B.	Function, Event
C.	Event, Function
D.	Event
Answer» D. Event

Discussion

108.	Which of the following property is associated with the Response event?$?
A.	responseStart
B.	responseEnd
C.	both responseStart and responseEnd
D.	none of the mentioned
Answer» D. none of the mentioned

Discussion

109.	What will happen if the browser encounters a script tag without an src attribute?$?
A.	Throws an error
B.	Throws an exception
C.	Sends it to the compiler
D.	Sends it to the interpreter
Answer» E.

Discussion

110.	Which of the below does not belong to the Render Engine work flow?$?
A.	Paint DOM elements
B.	Parse Content
C.	uild DOM nodes in render tree
D.	None of the mentioned
Answer» E.

Discussion

111.	What is the default value of the asyc attribute?$?
A.	0
B.	1
C.	False
D.	True
Answer» E.

Discussion

112.	Which of the following are client-side JavaScript object?$?
A.	Database
B.	Cursor
C.	Client
D.	FileUpLoad
Answer» E.

Discussion

113.	Why do we need to use an onload event in the script tag after using the async attribute?$?
A.	Invoke code during page loading
B.	Invoke code during script loading
C.	Invoke code during downloading
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

114.	What will happen if the browser encounters a script tag without an src attribute??
A.	Throws an error
B.	Throws an exception
C.	Sends it to the compiler
D.	Sends it to the interpreter
Answer» E.

Discussion

115.	Why do we need to use an onload event in the script tag after using the async attribute??
A.	Invoke code during page loading
B.	Invoke code during script loading
C.	Invoke code during downloading
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

116.	Which of the below does not belong to the Render Engine work flow??
A.	Paint DOM elements
B.	Parse Content
C.	uild DOM nodes in render tree
D.	None of the mentioned
Answer» E.

Discussion

117.	What is the default value of the asyc attribute??
A.	0
B.	1
C.	False
D.	True
Answer» E.

Discussion

118.	Which of the following are client-side JavaScript object??
A.	Database
B.	Cursor
C.	Client
D.	FileUpLoad
Answer» E.

Discussion

119.	What is the purpose of holding whatever tag you create in the attribute type?
A.	To have more information
B.	To identify the scripting language
C.	All of the mentioned
D.	None of the mentioned
Answer» C. All of the mentioned

Discussion

120.	Which of the following does JSON.stringify not serialize?
A.	Undefined values
B.	Functions within an object
C.	Both Undefined values and Functions within an object
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

121.	Which of the following does not serialize the undefined values or objects within an object?
A.	JSON.string
B.	JSON
C.	JSON.stringify
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

122.	What does the method Performance.now() return?
A.	DOMTimeStamp
B.	DOMHighResTimeStamp
C.	DOMStamp
D.	TimeStamp
Answer» C. DOMStamp

Discussion

123.	What is the purpose of the constant TYPE_RELOAD?
A.	Reload performed
B.	Reload not performed
C.	Reload must be performed
D.	None of the mentioned
Answer» B. Reload not performed

Discussion

124.	What is the purpose of the timing property in the window.performance object?
A.	Time of navigation event
B.	Time of page load event
C.	Time of navigation and page load event
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

125.	What is the purpose of using the async attribute in the script tag?
A.	Load the script asynchronously
B.	Load the script synchronously
C.	Load the page asynchronously
D.	Load the page synchronously
Answer» B. Load the script synchronously

Discussion

126.	What is the purpose of the method createDocumentFragment()?
A.	Creates a fragment object
B.	Creates a document fragment
C.	Creates imaginary node object
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

127.	What is the inital step to set up a CSS Lazy Loading?
A.	Fetching data
B.	Loading the script
C.	Loading the page
D.	Adding the event listener
Answer» B. Loading the script

Discussion

128.	What is the purpose of the property PerformanceTiming.navigationStart?
A.	Ready to end the navigation
B.	Ready to jump the navigation
C.	Ready for navigation
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

129.	How many properties does a prototype object have?
A.	6
B.	7
C.	8
D.	9
Answer» C. 8

Discussion

130.	What does the usedJsHeapSize property indicate?
A.	Amount of memory used
B.	Amount of memory unused
C.	Amount of memory used & unused
D.	None of the mentioned
Answer» B. Amount of memory unused

Discussion

131.	What does it indicate when the type attribute of the navigation object is set to 2?
A.	Navigation by moving back through history
B.	Navigation by moving forward through history
C.	Navigation by moving back & forward through history
D.	None of the mentioned
Answer» D. None of the mentioned

Discussion

132.	How many properties are available in a memory object?
A.	1
B.	2
C.	3
D.	4
Answer» D. 4

Discussion

133.	Which of the following property gives access to the JavaScript memory usage data?
A.	performance.memory
B.	memory(performance)
C.	performance(memory)
D.	none of the mentioned
Answer» B. memory(performance)

Discussion

Explore topic-wise MCQs in Javascript.

How many properties are there in the interface PerformanceTiming?$?

What can be done to monitor the memory usage?$?

What does the rendering engine do when it encounters JavaScript?$?

Which of the following is a read-only property?$?

What is the function of the memory object?$?

What does the constant TYPE_BACK_FORWRD indicate?$?

What are the parameters of the attachEvent function?$?

Which of the following property is associated with the Response event?$?

What will happen if the browser encounters a script tag without an src attribute?$?

Which of the below does not belong to the Render Engine work flow?$?

What is the default value of the asyc attribute?$?

Which of the following are client-side JavaScript object?$?

Why do we need to use an onload event in the script tag after using the async attribute?$?

What will happen if the browser encounters a script tag without an src attribute??

Why do we need to use an onload event in the script tag after using the async attribute??

Which of the below does not belong to the Render Engine work flow??

What is the default value of the asyc attribute??

Which of the following are client-side JavaScript object??

What is the purpose of holding whatever tag you create in the attribute type?

Which of the following does JSON.stringify not serialize?

Which of the following does not serialize the undefined values or objects within an object?

What does the method Performance.now() return?

What is the purpose of the constant TYPE_RELOAD?

What is the purpose of the timing property in the window.performance object?

What is the purpose of using the async attribute in the script tag?

What is the purpose of the method createDocumentFragment()?

What is the inital step to set up a CSS Lazy Loading?

What is the purpose of the property PerformanceTiming.navigationStart?

How many properties does a prototype object have?

What does the usedJsHeapSize property indicate?

What does it indicate when the type attribute of the navigation object is set to 2?

How many properties are available in a memory object?

Which of the following property gives access to the JavaScript memory usage data?