Chọn phương án thích hợp với câu ban đầuCâu hỏiSmallpox is a dangerous disease. Malaria is a dangerous disease. A. Smallpox is a dangerous disease, and so is malaria. B. Malaria is a dangerous disease, but smallpox is not. C. Neither smallpox nor malaria is a dangerous disease. D. Either smallpox or malaria is a dangerous disease.