Correct Answer: A

Rationale: A sagittal section divides the body into right and left regions. This type of section runs longitudinally from front to back, separating the body into right and left halves. Sagittal sections are crucial for understanding the anatomical structure and orientation of various body parts. Choices B, C, and D are incorrect because a sagittal section specifically divides the body into right and left portions, not upper and lower regions, front and back regions, or between the dorsal and ventral cavities.

Correct Answer: C

Rationale: A herniated lumbar disc is most likely to cause pain along the sciatic nerve. The sciatic nerve is a long nerve that extends from the lower back down the back of each leg. Compression of the sciatic nerve by a herniated disc can lead to symptoms such as pain, numbness, tingling, or weakness that radiates down the leg. This condition is commonly referred to as sciatica. Choices A, B, and D are incorrect because a herniated lumbar disc typically affects the sciatic nerve, not the radial nerve, spinal cord, or tibial nerve.

Correct Answer: A

Rationale: Pepsin is an enzyme produced in the stomach that is essential for breaking down proteins during digestion. It functions by breaking down large protein molecules into smaller peptides, which are further broken down into amino acids for absorption in the intestines. Therefore, option A, 'To break down proteins,' is the correct answer. Choices B, C, and D are incorrect as they do not align with the specific function of pepsin in the body.

Correct Answer: B

Rationale: The tympanic membrane, also known as the eardrum, is the most medial feature in the ear. It separates the outer ear from the middle ear and serves as a barrier that vibrates in response to sound waves, transmitting vibrations to the middle ear ossicles. The pinna, cochlea, and outer canal are located more laterally in the ear anatomy. The pinna is the visible part of the ear located on the lateral side of the head, the cochlea is a spiral-shaped structure in the inner ear responsible for hearing, and the outer canal refers to the external auditory canal leading to the eardrum.

Correct Answer: D

Rationale: The correct answer is D: reproductive system. The ovaries are essential organs of the female reproductive system. They play a vital role in producing eggs and secreting hormones like estrogen and progesterone. The skeletal system (choice A) consists of bones and tissues that support the body, the nervous system (choice B) controls body functions and responses, and the lymphatic system (choice C) helps the body fight off infections. Therefore, the ovaries belong to the reproductive system.