In 1947, pilot Chuck Yeager became the first person in an airplane to fly faster than the speed of sound. He flew his plane about 12,000 meters above sea level. At that altitude, the speed of sound travels at 290 meters/second. At sea level, the speed of sound is about 340 meters/second. What conclusion can you make from this information?
A The speed of sound does not depend on altitude.
B The speed of sound depends on the type of plane flown.
C As the altitude increases, the speed of sound increases.
D As the altitude increases, the speed of sound decreases.