Which revision correctly combines these two sentences?
There was a lot of traffic today. It took an hour to get home.

A. There was a lot of traffic today and it took an hour to get home.
B. There was a lot of traffic today; it took an hour to get home.
C. There was a lot of traffic today, it took an hour to get home.
D. There was a lot of traffic today it took an hour to get home.