Concept:The idiom "backed the wrong horse" means supporting someone who turns out to be unsuccessful or unsuitable.Explanation:The expression is figurative and comes from horse racing.In racing, to "back" a horse means to bet on it or support it.In everyday language, "backing the wrong horse" means giving your support to the wrong person or cause.So, Buba clearly supported someone who was not the right or winning choice.Answer:A. supported the wrong person