Concept:Idioms are phrases whose meaning differs from their literal words. "Blow one's own horn" is a common English idiom for self-praise.Explanation:The idiom means to boast or praise oneself excessively. It comes from the idea of a musician blowing a horn to announce their own arrival. Option A directly matches this meaning. Option B is the literal act of playing an instrument, but the idiom is figurative. Option C describes helping others, which is not related. Option D means staying silent, the opposite of bragging. Therefore, only Option A is correct.Answer:A. To praise oneself excessively