Correct Answer: A

Rationale: In the context provided, 'deceptive' means misleading. The passage discusses how the Federal Trade Commission (FTC) regulates product advertising to ensure that all information is truthful and not misleading. Therefore, the correct answer is 'A: misleading.' Choice B, 'malicious,' is incorrect as it implies harmful intent, which is not necessarily conveyed by the term 'deceptive' in this context. Choice C, 'illegal,' is incorrect because 'deceptive' does not solely refer to something being against the law, but rather to misleading information. Choice D, 'irritating,' is also incorrect as it does not capture the essence of 'deceptive' as used in the passage.

Correct Answer: A

Rationale: In the context of the immune system, 'enlist' means to call into service. Immune cells recruit other cells to fight infection by producing chemicals that regulate their growth, behavior, and direct new recruits to trouble spots. This process is essential for the immune system's defense mechanism. The other choices are incorrect: 'write down' and 'put across' do not capture the action of mobilizing immune cells, and 'send away' is opposite in meaning to what is happening in the immune response.

Correct Answer: C

Rationale: The author's primary purpose in writing the essay is to inform the reader about how an electrocardiograph reads the electric currents emitted by the heart. Choice A is incorrect because there is no attempt to persuade the reader to have an ECG. Choice B is incorrect because the essay is focused on providing information rather than entertaining with a heartwarming story. Choice D is incorrect as the essay does not primarily analyze the difference between the SA node and the AV node; instead, it focuses on explaining how an electrocardiograph reads electric currents from the heart.

Correct Answer: D

Rationale: In the context provided, 'popular' refers to magazines intended for the general public. The paragraph mentions that Infotrac indexes hundreds of popular magazines and newspapers, including medical journals such as the Journal of the American Medical Association and New England Journal of Medicine. These magazines target a wide audience, making choice D ('for the general public') the correct answer. Choices A, B, and C are incorrect as they do not align with the context of the paragraph.

Correct Answer: D

Rationale: In this context, 'ideal' means perfect. The human body provides a perfect environment for many microbes, as stated in the extract. It is the immune system's role to keep these microbes out or destroy them. The other choices are incorrect: 'thoughtful' does not fit the context of the sentence, 'confined' and 'hostile' are not synonymous with 'ideal' in this context.