Consider a relational table with a single record for each registered student with the following attributes: 1. Registration_Number: Unique registration number for each registered student 2. UID: Unique Identity Number, unique at the national level for each citizen 3. Bank Account_Number: unique account number at the bank. A student can have multiple accounts or joint accounts. This attributes stores the primary account number 4. Name: Name of the Student 5. Hostel_Room: Room number of the hostel Which of the following options is incorrect?

Registration Account_Number can be primary key

Bank Account_Number is a candidate key

Registration Account_Number can be primary key

UID is a candidate key if all students are from the same country

If S is a superkey such that S UID is NULL then S UID is also a super key

Consider a relational table with a single record for each registered s

1.	Consider a relational table with a single record for each registered student with the following attributes: 1. Registration_Number: Unique registration number for each registered student 2. UID: Unique Identity Number, unique at the national level for each citizen 3. Bank Account_Number: unique account number at the bank. A student can have multiple accounts or joint accounts. This attributes stores the primary account number 4. Name: Name of the Student 5. Hostel_Room: Room number of the hostel Which of the following options is incorrect?
A.	Bank Account_Number is a candidate key
B.	Registration Account_Number can be primary key
C.	UID is a candidate key if all students are from the same country
D.	If S is a superkey such that S UID is NULL then S UID is also a super key
Answer» B. Registration Account_Number can be primary key

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