Correct Answer: C

Rationale: The simple columnar epithelium lining the small intestine is crucial for absorption. This type of epithelium is specialized for absorption due to its tall and closely packed cells, which increase the surface area available for nutrient absorption. The primary function of the small intestine is to absorb nutrients from digested food, and the simple columnar epithelium's structure aids in this process by providing a large surface area for absorption. Choices A, B, and D are incorrect because movement, support, and insulation are not primary functions associated with the simple columnar epithelium in the small intestine. While these functions are essential in other tissues or organs, absorption is the key role of the simple columnar epithelium in the small intestine.

Correct Answer: B

Rationale: As a water wave approaches a shallow beach, the speed of the wave decreases due to the change in medium from deep to shallow water. According to the wave equation (speed = frequency x wavelength), if the speed decreases and the frequency remains the same, the wavelength must also decrease to maintain the equation balanced. This phenomenon occurs due to the wavefronts being slowed down by the shallower water, causing the wavelength to decrease while the frequency remains constant. Choice A is incorrect as the speed of the wave decreases in shallow water. Choice C is incorrect because the speed increases in deep water, not in shallow water. Choice D is incorrect as all the wave characteristics change when moving from deep to shallow water.

Correct Answer: A

Rationale: The tonsils and adenoids are part of the lymphatic system, not the respiratory, endocrine, or digestive systems. The lymphatic system plays a crucial role in the body's defense against infections and diseases by producing white blood cells and lymphatic fluid, which help in filtering harmful substances. The respiratory system is primarily responsible for breathing and gas exchange in the body, the endocrine system regulates hormones, and the digestive system is involved in the breakdown and absorption of nutrients from food. Therefore, the correct answer is the lymphatic system.

Correct Answer: C

Rationale: The simple columnar epithelium lining the small intestine is crucial for absorption. This type of epithelium is specialized for absorption due to its tall and closely packed cells, which increase the surface area available for nutrient absorption. The primary function of the small intestine is to absorb nutrients from digested food, and the simple columnar epithelium's structure aids in this process by providing a large surface area for absorption. Choices A, B, and D are incorrect because movement, support, and insulation are not primary functions associated with the simple columnar epithelium in the small intestine. While these functions are essential in other tissues or organs, absorption is the key role of the simple columnar epithelium in the small intestine.

Correct Answer: C

Rationale: The correct answer is the uterus. The uterus is a muscular organ in the female body where a developing fetus is nourished and protected during pregnancy. It is the site where a fertilized egg implants and grows into a fetus. The ovaries produce eggs, the fallopian tubes transport the egg to the uterus for potential fertilization, and the vagina serves as the birth canal and the passage for menstrual blood to exit the body. Therefore, the uterus plays a crucial role in pregnancy by providing a nurturing environment for the developing fetus.