Can JavaScript identifiers include spaces?
A). Yes
B). No
C). Only in ES6
D). Only in strings
Is let a valid identifier in JavaScript?
A). Yes
B). No
C). Only in ES6
D). Only in non-strict mode
What will the following code output: var x; x = 5; var y = x;
A). undefined
B). null
C). 5
D). x
What is a valid identifier in JavaScript?
A). 123abc
B). abc123
C). let
D). var
Can an identifier be a single character?
A). Yes
B). No
C). Only in ES5
D). Only in ES6
Which of the following is a valid identifier?
A). if
B). else
C). null
D). value1
Which of the following is a reserved word in JavaScript?
A). myVariable
B). function
C). let
D). number
Which characters are allowed in JavaScript identifiers?
A). Letters only
B). Letters and numbers only
C). Letters, numbers, $ and _
D). Any special characters
Are JavaScript identifiers case-sensitive?
A). Yes
B). No
C). Only in ES6
D). Only in strict mode
What will happen if you declare a variable with the name undefined?
A). Syntax error
B). Declares a variable
C). Throws a runtime error
D). Reassigns undefined