Which of the following represents an arithmetic sequence?

A.The temperature rises one degree the first hour, 2 degrees the second hour, 4 degrees the third, and so on.
B. The temperature rises two degrees the first hour, another two degrees the second hour, and so on.
C. The temperature rises by one degree the first hour and then falls two degrees the second hour.
D. The temperature rises and falls at different rates during the day.