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 men knew that wolves were out and had noticed them. This speaks to the theme of danger and chaos in the wild. The wild is not dictated by the rules of man: it is wild and unpredictable.
Answer:
If you have more education(e.g. a PhD versus a Master degree), and a better school(e.g. Stanford vs UCSF), then you can get higher paying jobs, and a wider variety of jobs.
Hope this helps!