Do you need help with homework
To me it like if your first you get more closer to success
"Why" is the question to ask to help identify the reason for an event that happens in a historical text.
If you ask "why" an event happened, you will get to better understand the reasoning around it, what prompted the event, and some of the personal/political emotions or decisions that surrounded the event.
Answer: B is your answer.. I know it can never be the last two.