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

I had to lose some weight. I went on a strict diet.

A. to not follow

B. not to following

C. to follow not

D. to following not

A. Having been on a diet, I went to the surgery.

B. I went to the surgery, so I asked the doctor about going on a diet.

C. I asked the doctor about going on a diet, so I went to the surgery.

D. I went to the surgery in order to ask about going on a diet.

A. enrolled

B. enroll

C. enrolling

D. to enroll

A. not thinking

B. to think not

C. not to think

D. not think

A. Tam says that we'll boost our immune system if we exercised regularly.

B. Tam said that we'd boost our immune system if we exercised regularly.

C. Tam said that we'll boost our immune system if we exercised regularly.

D. Tam said that we boost our immune system if we exercised regularly.

A. I wore a warm coat and a scarf though I didn't want to catch a cold.

B. I wore a warm coat and a scarf, so I didn't want to catch a cold.

C. I wore a warm coat and a scarf, but I didn't want to catch a cold.

D. I wore a warm coat and a scarf in order not to catch a cold.

A. Mai's father said she would recover quickly if she follows the doctor’s advice.

B. Mai's father said she will recover quickly if she followed the doctor's advice.

C. Mai's father said she would recover quickly if she followed the doctor's advice.

D. Mai's father says she would recover quickly if she followed the doctor's advice.