If you cannot remember formula for group velocity, at least you should remember that it somehow represents "physical" velocity, while phase velocity can be greater than, say, the speed of light in vacuum.
Hence, it is likely that (A), (B), and (D) are wrong.
You may guess (C) or (E) as an answer.
Actually, the group velocity is defined as

. Looking at behavior when

is very large (i.e.

is negligible),

. Hence, as

, group velocity goes to

.
Note that checking limit behavior is a good strategy. Do not try tedious derivative without checking limit behavior first.
The correct answer is (E). 41 of 100 people chooses this correct choice.