Answer:
A) it makes a verb an adjective
Explanation:
It makes the verb an adjective because if you have "fast" and put in "-er" you'd get "faster". Faster would mean going more vigoriously than before, therefore describing the speed of "fast"
1) teeth
2)drain
3)jiggle
4)brownies
5) chaos
6)rapidly
7) egg roles
8)hedgehog
9) sisters
10)goodies
Because all start with same letter from previous word
Hope this helped
D. The others answer only parts of it and d explains it as a whole