Answer:
There is no passage so I cannot answer the question please repost the passage and I would love to help you.
Am I reading the question wrong.
The answer is A.
The correct answer is becoming an astronomy researcher
For starters, it is the only appositive phrase. It is also non-essential because the sentence conveys full meaning even if it was removed.
Answer: The forest growth in the understory was thick and dense; it was difficult to find the trail.
