Answer:
The sentence which correctly uses the word "coma" as it might be found in Brianna's textbook is:
C. The coma of the comet consists of ice particles and interstellar dust.
Step-by-step explanation:
The definition in Brianna's textbook clearly refers to "coma" as being that dust cloud that surrounds a comet. Therefore, we need to find a sentence that somehow mentions a comet's coma.
Sentences A and D can be eliminated since they refer to the coma a person gets into after an accident or due to an illness, for example. Sentence B refers to punctuation marks. In this case, it should be "comma" and not "coma". We can eliminate it as well. We are left with option C, which is the only one that uses coma in the sense found in the glossary. It clearly speaks of the coma of a comet.