Noxious, objectionable, or disgusting animals collectively, especially those of small size that appear commonly and are difficult to control, as flies, lice, bedbugs, cockroaches, mice, and rats. ... etc . Idk If this helps any but I tried!
Answer:
I think B is the best description of chromosomes because it describes them and gives relevent information about what they do.
A parenthetical element is a part of a sentence that can be removed without changing the meaning of the sentence.
