Q
Which of the following variable names is valid in JavaScript?

Answer & Solution

Answer: Option b
Solution:
Variable names in JavaScript can contain letters, digits, underscores, and dollar signs, but they cannot start with a digit. The correct option is b. _variable.
Related Questions on Average

Which keyword is used to declare a variable that cannot be reassigned in JavaScript?

A). a. var

B). b. let

C). c. const

D). d. mutable

What keyword is used to declare variables in JavaScript?

A). a. var

B). b. const

C). c. let

D). d. def

What does hoisting refer to in JavaScript variable declarations?

A). a. Declaring a variable multiple times

B). b. Initializing a variable before declaring

C). c. Moving variable declarations to the top

D). d. Using undeclared variables

Which keyword is used to declare a variable that cannot be reassigned in JavaScript?

A). a. var

B). b. let

C). c. const

D). d. mutable

Which of the following variable names is valid in JavaScript?

A). a. my variable

B). b. _variable

C). c. 3variable

D). d. variable$

What will console.log(a); output if a is declared outside a function but inside a block using let in JavaScript?

A). a. It will output the value of a

B). b. It will throw an error

C). c. It will output undefined

D). d. It

What keyword is used to declare variables in JavaScript?

A). a. var

B). b. const

C). c. let

D). d. def

What will happen if you try to reassign a value to a constant declared with const in JavaScript?

A). a. It will throw an error

B). b. It will silently ignore the assignment

C). c. It will convert the variable to let

D). d. It will convert the variable to var

What is the outcome of console.log(typeof x); if x is declared but not initialized in JavaScript?

A). a. Undefined

B). b. Null

C). c. Error

D). d. Object

Which of the following statements is true about the let keyword in JavaScript?

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

B). b. Variables declared with let are block-scoped

C). c. let is used to declare constants

D). d. let is used to declare functions