Answer:
Option C, Kidneys
Step-by-step explanation:
Kidney is very essential as it regulates the fluid content in our body; it also filters out essential nutrients from the blood; filters waste material from food and also regulate blood pressure. In the model, it is depicted that solid material is filtered out form the liquid. This process conjugates with the filtering process of kidneys.
Heart is responsible for pumping blood, glands secrete hormones and stomach digest food.
Option C is correct