The room became hotter and hotter. I had to...

Câu hỏi: The room became hotter and hotter. I had to take off my sweater.

A. Unless the room became hotter and hotter, I had to take off my sweater. 

B. Although the room became hotter and hotter, I had to take off my sweater. 

C. The room became hotter and hotter but I had to take off my sweater. 

D. The room became hotter and hotter so I had to take off my sweater.