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
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
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
Which keyword is used for declaring variables that should not change?
A). var
B). let
C). const
D). all of the above
What will be the output of the following code: let y = 10; let y = 20; console.log(y);
A). 10
B). 20
C). Error
D). undefined
What is the scope of a variable declared with 'let' inside a loop?
A). Global
B). Function
C). Loop block
D). Entire script
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: console.log(a); var a = 50;
A). 50
B). undefined
C). Error
D). null
How does 'let' handle variable re-declaration in the same scope?
A). Allows it
B). Silently ignores
C). Throws an error
D). Creates a new variable
What will be the output of the following code: const d = 90; d = 100; console.log(d);
A). 90
B). 100
C). Error
D). undefined