Viết lại các câu sau bằng những từ cho sẵn dưới đâyCâu hỏi He/ read/ book/ his room/ when/ he/ hear/ big explosion/. A. He was reading books on his room when he heard a big explosion. B. He read books in his room when he heard a big explosion. C. He was reading books in his room when he was hearing a big explosion. D. He was reading books in his room when he heard a big explosion.