Q
What will be the output of the code above?

Answer & Solution

Answer: Option C
Solution:
The Object.freeze() method prevents modifications to an object's properties. Attempting to modify person.age after freezing person will result in a TypeError because the object is now immutable.
Related Questions on Average

Which of the following statements is true about constants declared using const?

A). They can be reassigned multiple times

B). They are hoisted to the top

C). They are mutable

D). They are immutable

What will be the output of the code above?

A). 30

B). 31

C). Error

D). Undefined

Which statement about JavaScript's const is true?

A). const variables can be redeclared

B). const variables are globally scoped

C). const variables are mutable

D). const variables cannot be reassigned

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

A). var

B). let

C). const

D). block

What happens if you try to reassign a value to a constant declared using const?

A). SyntaxError

B). TypeError

C). ReferenceError

D). No error, value is reassigned

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

A). Variables declared with let have global scope

B). Variables declared with let have function scope

C). Variables declared with let are block-scoped

D). Variables declared with let are hoisted

What is the primary advantage of using block scope in JavaScript?

A). Reducing code size

B). Preventing variable hoisting

C). Avoiding global variables

D). Improving performance

Which of the following best describes the behavior of JavaScript's const keyword?

A). It prevents variables from being redeclared

B). It ensures variables cannot be reassigned

C). It provides global scope for variables

D). It allows variables to change their data type

What will be the output of the code above?

A). 10

B). 20

C). Error

D). Undefined

What is the benefit of using const over var in JavaScript?

A). const variables have function scope

B). const variables are hoisted to the top

C). const variables prevent accidental reassignments

D). const variables can be used anywhere