Correct Answer: B

Rationale: Basketball is not listed as a low-impact sport in the extract provided; the others (martial arts, yoga, and weight lifting) are considered low-impact activities. The extract mentions that students can participate in low-impact sports like yoga, martial arts, and weight lifting in modern PE classes, emphasizing their benefits and the focus on general skills. Basketball, on the other hand, is not included in the list of low-impact sports mentioned in the extract, making it the correct answer. This demonstrates the importance of understanding the difference between high-impact and low-impact sports for maintaining fitness and health.

Correct Answer: B

Rationale: The correct answer is B. The reader can infer that the 'sweatiest students' have worked harder during class. This inference is supported by the context that students are graded based on the effort they make in the class, with some even receiving extra credit for being the sweatiest students in the room. Choice A is incorrect as there is no indication in the passage that the sweatiest students are more physically active than others; they are recognized for their effort, not necessarily for being the most active. Choice C is incorrect as the passage does not discuss the academic performance of the sweatiest students. Choice D is incorrect as there is no evidence to suggest that the sweatiest students excel in all sports activities; they are acknowledged for their effort rather than their overall sports performance.

Correct Answer: A

Rationale: The correct answer is A: 'Impart.' In the context of the passage, 'instill' means to impart important lessons about maintaining good health, staying fit, and keeping weight under control. This word choice is appropriate as it aligns with the idea of teaching and passing on knowledge. Choice B, 'Propagandize,' is incorrect as it implies spreading biased or misleading information, which is not the intended meaning in this context. Choice C, 'Demand,' is incorrect as it does not capture the concept of teaching or passing on lessons. Choice D, 'Create,' is also incorrect as it does not convey the idea of imparting knowledge or lessons, which is the central meaning of 'instill' in this context.

Correct Answer: B

Rationale: The passage discusses the revision of the food pyramid specifically to address the unique dietary needs of seniors. It emphasizes how the changes were made based on ongoing research and analysis, indicating a broader focus on senior nutrition rather than just individual nutrients or exercise. Thus, option B captures the essence of the passage as it succinctly summarizes the main idea.

Correct Answer: A

Rationale: The main idea of the passage is that recent discoveries are shedding light on the pivotal role of microorganisms in maintaining a properly functioning immune system. The passage discusses how the human body hosts a wide array of microorganisms, emphasizes the importance of these bacteria in the development of the immune system, and explores the potential applications of bacteriotherapy. Choice A is the correct answer because it accurately reflects the central theme discussed in the passage. Choices B, C, and D are incorrect because they focus on specific details or applications mentioned in the passage, rather than capturing the overarching theme of the critical role of microorganisms in immune system function.