Explore topic-wise MCQs in Javascript.

This section includes 14 Mcqs, each offering curated multiple-choice questions to sharpen your Javascript knowledge and support exam preparation. Choose a topic below to get started.

1.

Consider the following code snippet :function constfunctions() { var functions = []; for(var k = 0; k < 10; k++) functions [k] = function() { return k; }; return functions ;}var functions = constfunctions();functions [5]()What does the last statement return ?

A. 10
B. 9
C. 0
D. All of above
E. None of these
Answer» B. 9
Discussion
2.

Consider the following code snippet :var p = counter(), q = counter(); p.count()q.count() p.reset() p.count() q.count()The state stored in q is :

A. Undefined
B. Null
C. 0
D. 1
E. None of these
Answer» E. None of these
Discussion
3.

What is the difference between the two lines given below ?!!(object1 && object2);(object1 && object2);

A. Both the lines checks just for the existence of the object alone
B. The first line results in a real boolean value whereas the second line merely checks for the existence of the objects
C. Both the lines result in a boolean value False
D. Both the lines result in a boolean value True
E. None of these
Answer» C. Both the lines result in a boolean value False
Discussion
4.

For the below mentioned code snippet:var obj = new Object();The equivalent statement is:

A. Object obj=new Object();
B. var obj= new Object;
C. var obj;
D. var obj = Object();
E. None of these
Answer» C. var obj;
Discussion
5.

Consider the following code snippet :var string2Number=parseInt("456pqr");

A. 456pqr
B. Exception
C. NaN
D. 456
E. None of these
Answer» E. None of these
Discussion
6.

Consider the following code snippet :var tensquared = (function(n) {return n*n;}(100));Will the above code work ?

A. Memory leak
B. Exception will be thrown
C. Error
D. Yes
E. None of these
Answer» E. None of these
Discussion
7.

Consider the following code snippet :var Total=eval("5*5+10");

A. 35 as an integer value
B. 35 as a string
C. Exception is thrown
D. 5*5+10
E. None of these
Answer» B. 35 as a string
Discussion
8.

Consider the following code snippetopt.fun(p,q);Which is an equivalent code for the above code snippet?

A. opt.fun(p && q);
B. opt(fun)["p","q"];
C. opt.fun(p) && opt.fun(q);
D. opt["fun"](p,q);
E. None of these
Answer» E. None of these
Discussion
9.

Consider the following code snippetfunction output(n) { for(var v in n) console.log(v + ": " + n[v] + " n");}What will the above code snippet result ?

A. prints only one property
B. Prints the contents of each property of n
C. prints the address of elements
D. Returns undefined
E. None of these
Answer» E. None of these
Discussion
10.

Consider the following code snippetfunction hypotenuse(p, q) { function square(n) { return n*n; } return Math.sqrt(square(p) + square(q));}What does the above code result?

A. Square of sum of p and q
B. Sum of p and q square
C. Sum of square of p and q
D. All of above
E. None of these
Answer» D. All of above
Discussion
11.

Which is an equivalent code to invoke a function fun of class opt that expects two arguments p and q?

A. opt.fun(p,q);
B. fun(p,q);
C. opt.fun(p) && opt.fun(q);
D. opt(p,q);
E. None of these
Answer» B. fun(p,q);
Discussion
12.

What is the difference between the two lines given below ?

A. Both the lines checks just for the existence of the object alone
B. The first line results in a real boolean value whereas the second line merely checks for the existence of the objects
C. Both the lines result in a boolean value False
D. Both the lines result in a boolean value True
E. None of these
Answer» C. Both the lines result in a boolean value False
Discussion
13.

Consider the following code snippet :

A. Undefined
B. Null
C. 0
D. 1
E. None of these
Answer» E. None of these
Discussion
14.

For the below mentioned code snippet:

A. Object obj=new Object();
B. var obj= new Object;
C. var obj;
D. var obj = Object();
E. None of these
Answer» C. var obj;
Discussion