The second option on the list is the correct one.
"Parallel sentence structure" basically means that the sentence uses repetitive phrasing and the two clauses will generally be close to the same length.
Answer:
Because Artemas needs to sail on the ship to Spain to find to find Damon's father who is fighting in Caesar's army.
Explanation:
This question is about The Wadjet Eye by Jill Rubalcaba that is a story about Damon and Artemas, two characters that begin a journey from Egypt to Spain to find Damon's father who is a soldier in Caesar's army to tell him about his mother's death. Artemas doesn't mind having to clean latrines in order to sail on the ship because he and Damon need to go to Spain to look for Damon's father.
The anwser is A... Therefore, he must leave early.
Probably B because if you use abbreviations you can type quicker but idk