Correct Answer: B

Rationale: The correct answer is B: 'To break down food.' The stomach plays a crucial role in the digestive system by breaking down food using gastric acid and digestive enzymes. This process transforms the food into a semi-liquid mixture known as chyme, which is further digested in the small intestine. Choices A, C, and D are incorrect because the stomach does not primarily absorb nutrients, produce bile, or store waste. These functions are carried out by other organs in the digestive system such as the small intestine, liver, and large intestine, respectively.

Correct Answer: B

Rationale: The correct answer is B: Absorbing water and forming solid waste. The large intestine plays a crucial role in absorbing water from the remaining indigestible food matter and forming solid waste (feces) to be excreted from the body. This process helps in maintaining the body's fluid balance and eliminating waste efficiently. Choices A, C, and D are incorrect because the large intestine is not primarily responsible for absorbing nutrients, breaking down fats, or secreting digestive enzymes. These functions are mainly carried out in the small intestine.

Correct Answer: B

Rationale: The correct answer is B: To secrete digestive enzymes. The pancreas plays a crucial role in digestion by secreting digestive enzymes that break down carbohydrates, fats, and proteins in the small intestine. These enzymes help in the process of breaking down food particles into smaller molecules that can be easily absorbed by the body for nutrients. Choices A, C, and D are incorrect as the primary function of the pancreas is not to absorb nutrients, produce bile, or store glucose in digestion.

Correct Answer: B

Rationale: The correct answer is B: Hyoid. The hyoid bone is the only bone in the body that does not articulate with any other bones. It is located in the neck and supports the tongue and other muscles involved in swallowing and speech. The scapula articulates with the clavicle and humerus, the radius with the ulna and humerus, and the femur with the pelvis and tibia. Choices A, C, and D are incorrect because they all articulate with other bones in the body.

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.