Sports physiologists at an Olympic training center wanted to monitor athletes to determine at what point their muscles were functioning anaerobically. They could do this by checking for a buildup of which of the following compounds?
A. ATP
B. Lactate
C. Carbon dioxide
D. ADP
E. Oxygen

B. Lactate

Explanation:

When we carry out strenuous physical activity, we begin to breathe heavily because our body prefers to generate energy using an aerobic method, in this way it tries to enter as much oxygen as possible, but in these physical activities that require effort, a greater amount of energy is needed. From which we can produce aerobically, this energy comes from glucose through glycolysis in which glucose is broken down or metabolized into a substance called pyruvate through a series of steps. When the body has plenty of oxygen, pyruvate is shuttled to an aerobic pathway to be further broken down for more energy, but when oxygen is limited, the body temporarily converts pyruvate into a substance called lactate, which allows glucose breakdown and thus energy production to continue.

answer; i believe its echoic memory,it is believed to last three to four seconds; good luck