Q
What is the behavior of accessing a var variable within a block before its declaration in JavaScript?

Answer & Solution

Answer: Option C
Solution:
Accessing a var variable within a block before its declaration results in printing undefined due to hoisting.
Related Questions on Average

How does hoisting differ between let and var declarations in JavaScript?

A). A. Both let and var variables are hoisted with their initial values

B). B. let variables are hoisted with their initial values, var variables are hoisted with undefined

C). C. let variables are not hoisted, var variables are hoisted with their initial values

D). D. Hoisting behavior is the same for let and var declarations

What happens if you access a var variable before its declaration in JavaScript?

A). A. ReferenceError

B). B. TypeError

C). C. undefined

D). D. No error

Which of the following is true about const variables in JavaScript?

A). A. They can be reassigned after declaration

B). B. They can be accessed before declaration

C). C. They cannot be declared without an initial value

D). D. They cannot be hoisted

What is the output of the following code snippet?

A). A. TypeError

B). B. 10

C). C. undefined

D). D. SyntaxError

What happens if you try to reassign a const variable in JavaScript?

A). A. No effect on the variable

B). B. SyntaxError is thrown

C). C. ReferenceError is thrown

D). D. TypeError is thrown

What is hoisting in JavaScript?

A). A. A process of lifting heavy objects

B). B. Moving variable and function declarations to the top of their scope

C). C. Reducing code size

D). D. None of the above

What is the purpose of the Temporal Dead Zone (TDZ) in JavaScript?

A). A. To prevent variable reassignment

B). B. To catch errors at compile time

C). C. To ensure variables are initialized before use

D). D. To reduce memory usage

How does hoisting affect function declarations in JavaScript?

A). A. Function declarations are hoisted with their function bodies

B). B. Function declarations are hoisted but cannot be accessed before declaration

C). C. Function declarations are not hoisted

D). D. Hoisting has no effect on function declarations

Which keyword allows hoisting of variables in JavaScript?

A). A. var

B). B. let

C). C. const

D). D. Both A and B

What is the behavior of accessing a const variable within a function before its declaration in JavaScript?

A). A. ReferenceError is thrown

B). B. SyntaxError is thrown

C). C. undefined is printed

D). D. No error