Answer:
B.) classification
Explanation:
In biology, classification is a way to organize living things. In science generally, this could expand to include any type of object.
When the muscle or the skeletal muscle cells undergo anaerobic respiration, they become painful and fatingued, it is now known to be caused by build up of lactate. The skeletal muscle will be painful and fatigued and the caused of it will be because by build up of lactate.