Choose the best answer to complete the following sentences.
16. That _______ ears are huge!

B: elephants'
A: elephant's

17. In the forest _____ all the branches were waving in the wind.

A: tree's
B: trees


18. The teacher looked at all the _______ work and chose the best artist.

A: student's
B. students

19. Where have I seen that ______ face before?
A: girl's
B: girls

20. All the ________ uniforms got dirty at that game
B: boys
A boy's