Correct Answer: A

Rationale: 'Imply' means to suggest or indicate something indirectly. In this context, 'Infer' (choice B) is incorrect as it means to deduce or conclude information based on evidence and reasoning, not to suggest. 'Opinion' (choice C) refers to a personal view or judgment, not the act of suggesting indirectly. 'Latter' (choice D) means the second of two things mentioned.

Correct Answer: A

Rationale: The correct answer is 'Refrain.' 'Refrain' is synonymous with 'abstain,' meaning to hold oneself back. The other choices are incorrect. 'Indulge' means to allow oneself to enjoy the pleasure of something, 'Adhere' means to stick to or follow, and 'Eliminate' means to completely remove or get rid of.

Correct Answer: C

Rationale: The correct answer is C, 'Surveillance,' which means 'under observation.' 'Cognition' (A) refers to mental processes, 'Isolation' (B) means being separated from others, and 'Assessment' (D) is the evaluation of something, none of which directly relate to being observed.

Correct Answer: C

Rationale: The sentence implies a cause-and-effect relationship, so 'because' is the appropriate conjunction. 'Nor' is used in negative constructions, 'Yet' indicates contrast, and 'So' is used to show a consequence, none of which fit the context of the sentence.

Correct Answer: D

Rationale: The correct answer is D: 'Soon to occur.' The word 'impending' is used to describe something that is about to happen or is soon to occur. In the context of the sentence provided, 'impending' operation indicates that the operation is about to take place. Choices A, B, and C are incorrect because 'impending' does not mean 'very serious,' 'required,' or 'elective.' Instead, it specifically refers to the timing of the operation as being imminent.