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

Answer & Solution

Answer: Option B
Solution:
You can change the properties of a constant object. Here, x.a is changed to 2.
Related Questions on Average

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];

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

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;

Can a constant objects properties be changed?

A). Yes

B). No

C). Only if redeclared

D). Only with special methods

How to increment a variable count by 1?

A). count + 1

B). count += 1

C). count =+ 1

D). count = 1

What does the assignment operator = do in JavaScript?

A). Compares two values

B). Assigns a value to a variable

C). Checks for equality

D). None of the above

What does let { a: alpha, b: beta } = { a: 1, b: 2 }; do?

A). Creates variables alpha and beta with values 1 and 2

B). Creates variables a and b with values 1 and 2

C). Throws an error

D). Assigns default values

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 is the outcome of let x = 8; x %= 3;?

A). 1

B). 2

C). 3

D). 5

Which operator assigns a remainder to a variable?

A). +=

B). -=

C). *=

D). %=