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 modifie In this case, person.age is modified to 31 and the output will be 31.
Related Questions on Average

What will happen when you try to execute this code?

A). 14 will be logged to the console

B). 14159 will be logged to the console

C). SyntaxError will occur

D). TypeError will occur

What will be logged to the console after executing the code above?

A). ['red', 'blue', 'green', 'yellow']

B). ['red', 'blue', 'green']

C). ['yellow']

D). Error

What does the const keyword signify in JavaScript?

A). Constant variable

B). Mutable variable

C). Global variable

D). Block-scoped variable

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

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

A). Function body

B). if statement body

C). while loop body

D). Object literal

What will be the output of the code above?

A). 10

B). 20

C). Error

D). Undefined

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 statements about const is true?

A). Variables declared with const can be reassigned

B). const variables have function scope

C). const variables cannot be used in loops

D). const variables are block-scoped

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

A). var

B). let

C). const

D). block

What will be the output of the code above?

A). 30

B). 31

C). TypeError

D). Undefined