Which function describes the digestive system?

The digestive system is primarily responsible for the process of breaking down food into smaller components that can be absorbed and utilized by the body. This system encompasses various organs, including the mouth, stomach, intestines, and others, which work together to ensure that nutrients are extracted from food and waste products are expelled from the body.

The functions of the digestive system can be summarized as absorbing nutrients and eliminating waste, which is precisely what the correct response highlights. Digestion is crucial for providing the body with essential nutrients like carbohydrates, proteins, fats, vitamins, and minerals, all of which are vital for growth, energy, and overall health. The removal of indigestible substances and metabolic waste is equally important to maintain the body's internal balance.

The other functions mentioned in the choices correspond to different systems in the body. For example, filtering blood to produce urine is a function of the urinary system, breathing in oxygen pertains to the respiratory system, and regulating body processes via hormones relates to the endocrine system. Therefore, the function of absorbing nutrients and eliminating waste distinctly identifies the vital role of the digestive system within the human body.