Mark the letter A, B, C or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
Coral reefs(A) are limestone formations(B) composed of tiny sea organisms(C) and the remains.(D)
A. Coral reefs
B. limestone formations
C. tiny sea organisms
D. the remains
Chọn D
“the remains” -> “their remains”. Nếu dùng là the remains thì trong câu không rõ nghĩa, “their remains” là chỉ “tiny sea organisms’ remains”