Question

animals produce a substance called insulin, which helps them maintain healthy levels of glucose in their blood.
insulin is most directly related to which function?
movement
feeding
reproduction
homeostasis

Explanation:

Insulin is a hormone that regulates blood - glucose levels. Homeostasis is the maintenance of a stable internal environment. Since insulin helps maintain a stable level of glucose (a key aspect of the internal environment), it is related to homeostasis. Movement is related to muscles and the nervous system. Feeding is related to the digestive system's intake of food. Reproduction is related to the reproductive organs and hormones like estrogen and testosterone.

Answer:

homeostasis