Q
What will be the output of the code above?

Answer & Solution

Answer: Option B
Solution:
Although person is a constant, its properties can be modified. In this case, person.age is modified to 31 and the output will be 31.
Related Questions on Average

What does the const keyword signify in JavaScript?

A). A. Constant variable

B). B. Mutable variable

C). C. Global variable

D). D. Block-scoped variable

What is the purpose of using the const keyword in JavaScript?

A). A. To declare variables with global scope

B). B. To declare block-scoped variables

C). C. To declare variables that can be reassigned

D). D. To declare variables that cannot be reassigned

What is the primary difference between const and let in JavaScript?

A). A. const variables can be reassigned

B). B. let variables are block-scoped

C). C. const variables are hoisted

D). D. let variables are immutable

What will be logged to the console after 1 second?

A). A. 0 1 2

B). B. 3 3 3

C). C. 0 0 0

D). D. Error

Which of the following is NOT an example of a block in JavaScript?

A). A. Function body

B). B. if statement body

C). C. while loop body

D). D. Object literal

What is the purpose of using block scope in JavaScript?

A). A. To declare constants

B). B. To prevent variable hoisting

C). C. To improve code performance

D). D. To create global variables

Which of the following statements is true about block scope in JavaScript?

A). A. Variables declared with let have global scope

B). B. Variables declared with let have function scope

C). C. Variables declared with let are block-scoped

D). D. Variables declared with let are hoisted

Which statement is true regarding the const keyword in JavaScript?

A). A. Constants declared with const are hoisted

B). B. Constants declared with const can be reassigned

C). C. Constants declared with const have global scope

D). D. Constants declared with const are immutable

Which keyword is used to declare block-scoped variables in JavaScript?

A). A. var

B). B. let

C). C. const

D). D. block

Which keyword is used to declare a constant array in JavaScript?

A). A. let

B). B. const

C). C. var

D). D. array