Concept:The correct option depends on the phrasal verb "came about," which means "happened."Explanation:"Come about" is a fixed phrasal verb meaning "to happen" or "to take place."So asking "how the accident came about" is the same as asking "how the accident happened."The words "up," "by," and "out" do not fit this context because they do not form a meaningful phrasal verb with "came" here.Thus, only "about" gives the sentence its correct meaning.Answer:Option D: about