C. accidental
Peterson had an accidental death
"In the late 1800's" is an introductory adverbial prepositional phrase. We can safely ignore it. All it does is modify the verb "were".
I believe the answer would be
B. diverse people contribute to the country's identity
Answer: Ok so they are all different, But what is 1 thing that makes them alike?
Explanation:
An adverb is an adjective + a verb. Meaning, it's a word that describes what someone/something is doing during the action.
A (whistle) & C (referee) are both nouns - person, place, or thing.
D (red) is just an adjective - describing something
B would make the most sense, it's telling you what the referee does with his whistle.
Hope this helped!