This actually depends on which level of education you are and what they are looking for. Most people though merely considers it a part of the Digestive System as the bile it stores is used during digestion.
I have seen however several people put it down as part of the bilary system or subsystem which responsible for the creation and distribution of bile.
Answer:
c. Prime mover strength
Explanation:
Based on the information provided within the question it can be said that this type of exercise is done in order to elicit Prime mover strength. This refers to the muscles that act as the main source and help increase the individuals stability, endurance, muscle growth, and strength. This is why individuals try to work this out during strength training.