What is the default scope of variables declared with the 'var' keyword in JavaScript?
A). Block scope
B). Function scope
C). Module scope
D). Block and function scope
Can 'const' be used to declare an array or object?
A). No, only primitives
B). Yes, but the reference can't change
C). Yes, and the content can't change
D). No
How does 'let' differ from 'var' in terms of scope?
A). No difference
B). Function-scoped
C). Block-scoped
D). Global-scoped
What will be the output of the following code: var e = 110; if (true) { var e = 120; } console.log(e);
A). 110
B). 120
C). Error
D). undefined
What will happen if you declare a variable without 'var', 'let', or 'const'?
A). Creates a global variable
B). Creates a block-scoped variable
C). Creates a function-scoped variable
D). Throws an error
Which keyword should be used by default to declare variables in modern JavaScript?
A). var
B). let
C). const
D). Either B or C
What will be the output of the following code: let c = 70; { let c = 80; console.log(c); } console.log(c);
A). 70 80 80
B). 80 80
C). Error
D). 70 80
Which of the following statements is true about 'const'?
A). It allows re-declaration
B). It allows reassignment
C). It is block-scoped
D). It is function-scoped
How do 'var' declarations handle hoisting?
A). They are not hoisted
B). Only the assignment is hoisted
C). Only the declaration is hoisted
D). Both declaration and assignment are hoisted
What will be the output of the following code: const z = 30; z = 40; console.log(z);
A). 30
B). 40
C). Error
D). undefined