Mark the letter A, B, C, or D to indicate the sentence that is best written from the words/ phrases given.Câu hỏi he/ retire/ eldest son/ take over/ business. A. After he retired, his eldest son took over his business. B. After retiring, his eldest son will take over his business. C. After he retires, his eldest son will take over a business. D. After he has retired, his eldest son took over a business.