Researchers Measure Cardiovascular Fitness with VO _{2 Max}

Researchers measure cardiovascular fitness with VO _{2 max} , which will:

A) remain the same when exercising at varying altitudes
B) increase the resting heart rate to pump blood more rapidly
C) decrease the amount of oxygen needed for exercising
D) indicate the level of improvement in muscle strength
E) increase as fitness improves and blood is pumped more efficiently