The bases of middle clouds are located at altitudes of between __________.

A
3,000 to 6,500 feet (914 to 1981 meters)
B
6,500 to 20,000 feet (1981 to 6096 meters)
C
10,000 to 35,000 feet (3048 to 10,668 meters)
D
20,000 to 60,000 feet (6096 to 18,288 meters)
E