Which of the Following Is a Correct Statement About the Energy

Which of the following is a correct statement about the energy systems and fuels used by the body? 

A)  After 20 minutes of sustained activity, fuel for the muscles primarily comes from glucose that is broken down by glycolysis. 
B)  About 90% of the fuel is derived from fat at rest. 
C)  All energy systems are used at all times, but one system which dominates depending on intensity and conditioning of athlete. 
D)  An anaerobic energy system is the most efficient way to fuel the body for prolonged activity. 
E)  The lactic acid system is the predominant source of energy after 3 minutes of activity and until activity has reached 20 minutes in length.