Correct Answer: B

Rationale: The correct answer is B: 'To filter waste from the blood.' The kidneys are vital organs responsible for filtering waste products from the blood, regulating fluid and electrolyte balance, and producing urine. Choice A is incorrect because the production of digestive enzymes primarily occurs in the pancreas and salivary glands. Choice C is incorrect as the production of white blood cells mainly takes place in the bone marrow and lymphatic system. Choice D is incorrect as the production of red blood cells occurs in the bone marrow.

Correct Answer: C

Rationale: The correct answer is the large intestine. The large intestine is responsible for absorbing water and forming feces from undigested food. The stomach's main function is to break down food with acid and enzymes. The small intestine is where most of the nutrients are absorbed into the bloodstream. The esophagus is the tube that connects the mouth to the stomach and does not play a role in absorbing water or forming feces.

Correct Answer: B

Rationale: The main function of the large intestine is to absorb water and form feces from waste material. Choice A is incorrect because the absorption of proteins primarily occurs in the small intestine. Choice C is incorrect as the production of enzymes for digestion mainly takes place in the pancreas and small intestine. Choice D is incorrect as the storage of fat is not a primary function of the large intestine.

Correct Answer: B

Rationale: The correct answer is the Hypothalamus (choice B). The hypothalamus plays a crucial role in maintaining homeostasis by regulating various bodily functions such as hunger, thirst, body temperature, and sleep cycles. While the brainstem (choice A) is involved in basic life functions like breathing and heart rate, it is not primarily responsible for maintaining homeostasis. The medulla oblongata (choice C) is part of the brainstem and controls vital autonomic functions like breathing and heart rate, but it is not the main regulator of homeostasis. The cerebrum (choice D) is responsible for higher brain functions such as thinking, memory, and voluntary movement, but it is not directly involved in maintaining overall bodily balance or homeostasis.

Correct Answer: D

Rationale: The correct answer is D: To regulate blood glucose. The adrenal glands play a crucial role in regulating blood glucose levels and the body's response to stress. Choice A, 'To regulate metabolism,' is incorrect as the primary role of the adrenal glands is not directly related to metabolism regulation. Choice B, 'To produce bile,' is incorrect because bile is produced by the liver, not the adrenal glands. Choice C, 'To produce red blood cells,' is also incorrect as the production of red blood cells primarily occurs in the bone marrow, not the adrenal glands.