Correct Answer: D

Rationale: In the context provided, 'defective' means faulty, referring to the gene that causes cystic fibrosis (CF). The passage explains that CF is caused by a defective gene, resulting in the production of abnormally thick and sticky fluid. The word 'defective' suggests that the gene is not functioning correctly, leading to the symptoms associated with the disease. Therefore, 'faulty' is the correct choice. The other options, 'unusual,' 'remarkable,' and 'postponed,' do not accurately capture the meaning of 'defective' in this context and are therefore incorrect.

Correct Answer: D

Rationale: In the context provided, 'defective' means faulty, referring to the gene that causes cystic fibrosis (CF). The passage explains that CF is caused by a defective gene, resulting in the production of abnormally thick and sticky fluid. The word 'defective' suggests that the gene is not functioning correctly, leading to the symptoms associated with the disease. Therefore, 'faulty' is the correct choice. The other options, 'unusual,' 'remarkable,' and 'postponed,' do not accurately capture the meaning of 'defective' in this context and are therefore incorrect.

Correct Answer: C

Rationale: In the context of the passage, 'massive' is used to describe the size of the collision that formed the Moon, indicating something very large or huge. While 'dense' means closely compacted, 'impressive' means evoking admiration, 'huge' is the closest synonym to 'massive' in this context. 'Unavoidable' does not convey the same meaning as 'massive' in this sentence, making it incorrect.

Correct Answer: B

Rationale: The correct answer is B. Matter at the nanoscale exhibits unique and special characteristics that distinguish it from matter at larger scales. This can include properties like increased surface area, different melting points, altered conductivity, and enhanced reactivity. Choice A is incorrect as metals at the nanoscale can be more rigid compared to their larger scale counterparts. Choice C is incorrect because matter at the nanoscale has properties that are distinct from both atomic and larger scales. Choice D is incorrect as there are significant differences in how matter behaves and interacts at the nanoscale compared to larger scales.

Correct Answer: B

Rationale: The correct answer is B. The passage highlights that damage to the limbic system, specifically the amygdala, can lead to passivity and lack of aggression. This is supported by the statement that patients with trauma or damage to the amygdala exhibit a complete absence of aggression. Thus, a stroke causing severe tissue damage in the limbic system, including the amygdala, can result in persistent passivity and imperturbability. Choices A, C, and D are incorrect because they do not directly relate to damage in the limbic system, which is specifically mentioned in the passage as the cause of the described behaviors.