Which type of figurative language is used in this sentence? Greta is a fish in the water, darting through the water with ease.
pun
simile
metaphor
Personification

Metaphor

Explanation:

A metaphor is a figure of speech that compares two things by saying the first thing is the second thing. Greta is obviously not actually a fish but she swims like one so the author used a metaphor.

WHY THE OTHER ANSWERS DO NOT WORK:

A pun is a joke exploiting the different possible meanings of a word. There is no joke being made here so the sentence is not a pun.

Personification is a form of metaphor in that human characteristics are attributed to nonhuman things. Greta is a human so this sentence is not an example of personification.

A simile is a figure of speech that compares two things using the terms "like" or "as". Neither of those phrases were used, so this sentence is not a simile.

The only option left is metaphor. :)