I believe it's being able to write for various contexts. It'll help you become a better writer.
D. Working as a flight attendant is the most exciting service job in the world. Someone else might think it's boring
What are the answer options?
Normally omniscient (3rd person pov) provides insight about the character's thoughts and motives, but sometimes 1st person can be helpful to gain information about how the character views the situation... Sorry if this seems confusing at all.
The two things a clause needed to considered a clause is a subject and verb.