Simplify the radical expression by rationalizing the denominator.

2 over square root 42
(1 point)
Responses

square root 84 over 42
Image with alt text: square root 84 over 42

square root 42 over 21
Image with alt text: square root 42 over 21

21 square root 42
Image with alt text: 21 square root 42

square root 2

2 square root 42 over 42