Here's why: A. comma- it will not be a comma because it doesn't make sense. B. dash- it is the correct answer, "School, sports, family- what more could this graduate want?" Sounds pretty good to me. C. semicolon- It sounds good to me, but not entirely correct. "School, sports, family; what more could this graduate want?" Semicolons are used to combine indepent clauses. D. period- you don't want to make it two sentences. Like this: School, sports, family. What more could this graduate want? It doesn't sound correct... and both will be incomplete sentences (or fragments).
I really hoped I helped! If you need more you could ask me. -Dawn