The answer is option D: adverb.
<em>Sometimes </em>is an adverb of frequency, which indicates how often something happens. Adverbs of frequency are usually used for repeated or periodic activities, so they often go with the present simple tense. Other examples of adverbs of frequency are: <em>always</em>, <em>usually</em>, <em>often </em>and <em>never</em>.
Answer: instituted an embargo of Cuba, forbidding Americans to trade with the country
Explanation:
The answer is D. Hope that helped.