What will be the output of the following code: const d = 90; d = 100; console.log(d);

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

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

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

Which keyword should be used by default to declare variables in modern JavaScript?

A). var

B). let

C). const

D). Either B or C

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

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 c = 70; { let c = 80; console.log(c); } console.log(c);

A). 70 80 80

B). 80 80

C). Error

D). 70 80

Can you re-declare a variable using 'const' in the same scope?

A). Yes

B). No

C). Only in functions

D). Only in loops

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

How does 'let' differ from 'var' in terms of scope?

A). No difference

B). Function-scoped

C). Block-scoped

D). Global-scoped