What does the assignment operator = do in JavaScript?

What will be the output of let { a, b } = { a: 1, b: 2, c: 3 };?

A). a is 1, b is 2

B). a is 2, b is 3

C). a is 1, b is undefined

D). a is 3, b is undefined

Which assignment will fail?

A). const x = 10; x = 20;

B). let y = 5; y = 10;

C). var z = 15; z = 30;

D). let a = { b: 2 }; a.b = 3;

Which of these correctly assigns values to variables using array destructuring?

A). [x, y, z] = [1, 2, 3]

B). [1, 2, 3] = [x, y, z]

C). let [x y z] = [1 2 3];

D). (x, y, z) = [1, 2, 3];

How to increment a variable count by 1?

A). count + 1

B). count += 1

C). count =+ 1

D). count = 1

How do you assign default values in destructuring?

A). let { a, b } = { a: 1 };

B). let { a = 1, b = 2 } = {};

C). let [a, b] = [1, 2];

D). let { a, b } = { a: 1, b: 2 };

What will be the value of x after the following code: let x = 10; x += 5;

A). 5

B). 10

C). 15

D). 20

Can a constant objects properties be changed?

A). Yes

B). No

C). Only if redeclared

D). Only with special methods

Which operator assigns a remainder to a variable?

A). +=

B). -=

C). *=

D). %=

What does const do in JavaScript?

A). Declares a block-scoped variable

B). Declares a constant value

C). Declares a global variable

D). Declares a function

What will const x = { a: 1 }; x.a = 2; do?

A). Throw an error

B). Change x.a to 2

C). Change x to 2

D). Do nothing