Mark the letter A, B, C or D to indicate the sentence that is closest in meaning to the original one.Câu hỏi She was so busy that she couldn't answer the phone. A. Because she was very busy, she could answer the phone. B. Although she was very busy, she could answer the phone. C. Because she was very busy, she couldn't answer the phone. D. Although she was very busy, she couldn't answer the phone.