Correct Answer: B

Rationale: The correct answer is B: To absorb water. The primary role of the large intestine is to absorb water from indigestible food matter. This absorption process helps in forming solid waste for excretion. Nutrient absorption primarily occurs in the small intestine, not the large intestine. Breaking down food and secreting digestive enzymes are functions primarily associated with the stomach and small intestine.

Correct Answer: A

Rationale: The larynx, also known as the voice box, is a crucial structure in the respiratory system. It is located in the upper part of the trachea and houses the vocal cords. The larynx plays a key role in producing sound and protecting the trachea by closing during swallowing to prevent food from entering the airway. This makes the larynx the correct answer in this context. The trachea (Choice B) is a respiratory structure that connects the larynx to the lungs, allowing air to pass through. The pharynx (Choice C) is a shared pathway for both air and food, located at the back of the throat. The esophagus (Choice D) is part of the digestive system, responsible for transporting food from the mouth to the stomach. Therefore, Choices B, C, and D are not located in the respiratory system.

Correct Answer: B

Rationale: Vitamin K is essential for the synthesis of proteins involved in blood clotting. These proteins help in the coagulation process, ensuring that wounds can heal properly by preventing excessive bleeding. Without sufficient Vitamin K, the blood clotting process may be impaired, leading to potential health risks. Vitamin D is important for bone health, Vitamin C is essential for the immune system and collagen production, and Vitamin B12 plays a role in red blood cell production and nerve function, but they are not directly involved in the blood clotting process.

Correct Answer: B

Rationale: The correct answer is B: To absorb nutrients. The small intestine's main role in the digestive system is to absorb nutrients from digested food. It has specialized structures, such as villi and microvilli, that increase its surface area for efficient absorption of nutrients into the bloodstream. Choice A is incorrect because the small intestine does not primarily secrete digestive enzymes; that role is mainly carried out by the pancreas and other digestive organs. Choice C is incorrect because the small intestine primarily absorbs nutrients rather than breaking down food. Choice D is incorrect because the absorption of water primarily occurs in the large intestine, not the small intestine.

Correct Answer: B

Rationale: The primary function of the heart is to pump oxygenated blood and nutrients throughout the body, supplying cells with vital substances. Choice A is incorrect as the kidneys are responsible for filtering blood. Choice C is incorrect as waste removal is primarily handled by organs like the kidneys and liver. Choice D is incorrect as regulating body temperature is mainly controlled by mechanisms such as sweating and shivering, not the heart.