Answer:
The noun the underlined participle modifies is:
b. aspects.
Explanation:
In the sentence we are analyzing here, there is a present participle, "troubling". A present participle is formed by adding -ing to a verb stem (interesting, caring, loving, etc.). Present and past participles can function as adjectives, modifying nouns or pronouns in a sentence. That is precisely the case here, where "troubling" is modifying the noun "aspects", attributing a quality to it. For that reason, we can choose letter B as the best option.
He probably uses a metaphor because a simile uses the words like and as and a metaphor does not use the words like and as. Hope this helps!
The idea of eating grasshoppers and crickets may inflict horror on some people but many others view insects as sustainable sources of protein.