The correct answer would be C
Clumps, waves are the two plural nouns.
B. an original research report
B) a waiting period in which a new firefighter undergoes several interviews
1) Prefix "a-" means "without, not". The meaning of the word "apathetic" is "without emotion or feeling";
2) In the word "analgesic", prefix "a-" denotes the process of removing or eliminating something. So, "analgesic" means "a medicine to remove pain";
3) Prefix "ex-" has the meaning "out". That is why, the word "expulsion" is defined as "to drive out";
4) Prefix "endo-" means "inside, within". Consequently, "endodermis" is the name of the inner layer of skin.
