___________ is the study of all life forms.

Correct Answer: C

Rationale: The correct answer is C: Biology. Biology is the study of all life forms, including their structure, function, growth, and evolution. Anatomy (choice A) focuses on the structure of living organisms, while Physiology (choice B) studies the functions of living organisms. Geology (choice D) is the study of the Earth's physical structure and substance, not life forms. Therefore, the correct choice is C as it encompasses the study of all life forms.

Correct Answer: C

Rationale: The correct answer is C: Chickenpox in a person who has never had it. The shingles virus, also known as herpes zoster, is caused by the reactivation of the varicella-zoster virus, which initially causes chickenpox. When the virus reactivates, it can lead to a painful rash and blisters, known as shingles, particularly in individuals who have had chickenpox before. Scabs due to tiny mites (A), abrasion due to friction (B), and severe fungal infections (D) are unrelated to the shingles virus and do not align with its characteristic symptoms.

Correct Answer: C

Rationale: The correct answer is C: Carbon dioxide. The lungs exchange oxygen from the air we breathe with carbon dioxide produced by our cells. Oxygen is taken up by red blood cells in the lungs and transported to the body tissues, while carbon dioxide is released from the tissues into the bloodstream and then exhaled through the lungs. Nitrogen (choice A) is not involved in the gas exchange process. Hydrogen (choice B) is not a primary gas exchanged during respiration. Carbon monoxide (choice D) is a toxic gas that can interfere with oxygen transport but is not a normal part of the respiratory exchange process.

Correct Answer: A

Rationale: The correct answer is A: Brain. The brain is a crucial component of the central nervous system, responsible for processing information, controlling bodily functions, and regulating emotions. It is the main organ that coordinates all activities in the body. Nerves (choice B) are part of the peripheral nervous system, not the central nervous system. Eyes and ears (choice C) are sensory organs that transmit information to the brain but are not part of the central nervous system. The autonomic nervous system (choice D) is a division of the peripheral nervous system that controls involuntary bodily functions, such as heart rate and digestion, and is not part of the central nervous system.

Correct Answer: C

Rationale: The correct answer is C: Iodine. Iodine is essential for thyroid hormone production, which regulates metabolism. Common table salt is often iodized to prevent iodine deficiency. Potassium (A) is important for heart and muscle function, but not specifically for thyroid function. Magnesium (B) plays various roles in the body but is not directly related to thyroid function. Copper (D) is involved in enzyme function but is not a primary mineral for thyroid gland function.