Answer:
The correct answer is - A. increase the size of the muscle cells and the amount of blood that is delivered to the muscle.
Step-by-step explanation:
Muscular endurance is the ability of a muscle to do some work or exert force continuously and rapidly for a period of time. To increase muscular endurance no heavy exercise required by including exercises that can help in increasing the size of the muscle cells and the amount of blood that is delivered to the muscle. The size of cells and delivering a high amount of blood helps in getting more oxygen and perform the metabolic activity more and generate more energy. So including the exercise rapidly and continuously will help in increasing the muscle cells.