Which of the following is an invalid identifier?

Which identifier is valid in strict mode?

A). public

B). _public

C). 123public

D). public$

Can JavaScript identifiers include spaces?

A). Yes

B). No

C). Only in ES6

D). Only in strings

Which is a correct identifier for a variable?

A). 9variable

B). variable-9

C). variable_9

D). variable 9

What is the maximum length of an identifier?

A). 255 characters

B). 31 characters

C). 64 characters

D). No limit

Are JavaScript identifiers case-sensitive?

A). Yes

B). No

C). Only in ES6

D). Only in strict mode

Which of these is an invalid identifier?

A). foo_bar

B). fooBar

C). foo-bar

D). foo$bar

Is let a valid identifier in JavaScript?

A). Yes

B). No

C). Only in ES6

D). Only in non-strict mode

Can an identifier be a single character?

A). Yes

B). No

C). Only in ES5

D). Only in ES6

What is a valid identifier in JavaScript?

A). 123abc

B). abc123

C). let

D). var

Which of the following is a valid identifier?

A). if

B). else

C). null

D). value1