Question #N1079

The following text is from Bram Stoker’s 1897 novel _Dracula_. The narrator is being driven in a carriage through a remote region at night. The baying of the wolves sounded nearer and nearer, as though they were closing round on us from every side. I grew dreadfully afraid, and the horses shared my fear. The driver, however, was not in the least disturbed; he kept turning his head to left and right, but I could not see anything through the darkness.

Which choice best combines the two sentences at the end of the passage into a single sentence with correct punctuation?
A. The driver, however, was not in the least disturbed; he kept turning his head to left and right, but I could not see anything through the darkness.
B. The driver, however, was not in the least disturbed, he kept turning his head to left and right, but I could not see anything through the darkness.
C. The driver, however, was not in the least disturbed, but I could not see anything through the darkness as he kept turning his head to left and right.
D. The driver, however, was not in the least disturbed, and, although he kept turning his head to left and right, I could not see anything through the darkness.