Mark the letter A, B, C or D on your answer sheet to indicate the sentence that best combines the pair of sentences given in each of the following questions.

His academic record at high school was poor. He failed to apply to that prestigious university. 

A. His academic record at high school was poor as a result of his failure to apply to that prestigious university. 

B. Failing to apply to that prestigious university, his academic record at high was poor. 

C. His academic record at high school was poor because he didn’t apply to that prestigious university.

D. His academic record at high school was poor; as a result, he failed to apply to that prestigious university. 

Trùng hợp hiđrocacbon nào sau đây tạo ra polime dùng để sản xuất cao su buna?

A. 2-metylbuta-1,3-đien C H 2 = C C H 3 - C H = C H 2

B. Penta-1,3-đien C H 2 = C H - C H = C H - C H 3 .

C. But-2-en C H 3 C H = C H C H 3 .

D. Buta-1,3-đien.