Its also known as imagery
The correct answer should be A. He was occupied with making sure his sister did not repeat the same error, otherwise.
This should be the correct answer because placing otherwise here would create confusion in the sentence as it is not sure to what it refers.
Viola most likely chose to disguise herself as a man because, at the time, men were viewed as more superior to women and women were often seen as weak and frail compared to men.
Hope this helps!
A. To enlighten that is the purpose