Correct Answer: C

Rationale: Reproduction is the most important process for the continuation of the human species as it involves the creation of new individuals. Without reproduction, the human species would cease to exist. Responsiveness and movement are essential for individual survival and functioning but do not directly impact the continuation of the species. Respiration is crucial for obtaining energy but is not directly linked to the continuation of the species.

Correct Answer: A

Rationale: An anatomist focuses on observing the structure and morphology of body parts, such as organs, tissues, and cells, to understand their organization. On the other hand, a physiologist is more concerned with studying the functions and processes of these body parts, including how they work individually and together to maintain homeostasis. Therefore, the correct answer is 'observing body parts; studying functions of body parts.' Choices B, C, and D are incorrect as they do not accurately reflect the primary activities of anatomists and physiologists.

Correct Answer: B

Rationale: Absorption is the process of taking in substances such as nutrients or gases. Exhaling carbon dioxide is a part of the process of respiration, not absorption. Therefore, the statement that absorption is the ability to exhale carbon dioxide is false. Choice A is incorrect because absorption does not involve exhaling carbon dioxide. Choice C is incorrect as the concept of absorption can be clearly defined. Choice D is also incorrect as there is a definitive answer to the statement provided.

Correct Answer: D

Rationale: Metabolism refers to all the chemical reactions that take place within an organism to sustain life, including processes such as breaking down molecules, building new molecules, and energy production. Choice A is incorrect because it describes excretion rather than metabolism. Choice B is incorrect as it specifically refers to the breakdown of substances, not encompassing the entirety of metabolic processes. Choice C is incorrect as it focuses solely on nutrient intake, which is just one aspect of metabolism.

Correct Answer: C

Rationale: The correct answer is C: Absorption of nutrients. The main function of the digestive system is to break down food into nutrients that can be absorbed by the body. Choice A, 'Formation of cells,' is incorrect as cell formation is not the primary function of the digestive system. Choice B, 'Movement of body parts,' is incorrect as this is more related to the muscular system. Choice D, 'Providing oxygen for the extraction of energy from nutrients,' is incorrect because providing oxygen is primarily the function of the respiratory system, not the digestive system.