Concept:The blank needs a word that shows contrast between Musa’s unwillingness and his mother’s action.
Explanation:"Even" cannot connect two independent clauses in this way.
"Otherwise" means "if not," which does not fit the meaning.
"Moreover" adds information instead of showing contrast.
"Nevertheless" means "in spite of that" or "however."
Musa did not want to fetch water, but his mother still made him do it.
So the sentence becomes: Musa did not want to fetch water for his grandfather; nevertheless, his mother made him do it.
Answer:C. nevertheless