Correct Answer: A

Rationale: The word 'did' is correctly used in the sentence to form the past tense of the verb 'do.' In this context, 'did' is the appropriate term. The other words in the sentence, 'work,' 'asked,' and 'before,' are all used correctly and do not represent an incorrect word choice. Therefore, 'did' is the only word that is not used incorrectly in the given sentence.

Correct Answer: A

Rationale: The correct answer is A: 'Thick and sticky.' Viscous describes a substance that is thick and sticky, resisting flow easily. Choices B, C, and D are incorrect. 'Slimy' implies a slippery, gooey texture; 'Watery' describes a substance with a thin, fluid consistency; and 'Dry' indicates the absence of moisture.

Correct Answer: B

Rationale: The correct answer is B: 'Obvious or easily observed.' Overt means something that is not hidden or concealed but rather openly displayed or easily noticed. Choice A, 'Hidden,' is the opposite of overt. Choice C, 'Barely noticeable,' implies something not overt but rather subtle. Choice D, 'Misleading,' is unrelated to the definition of overt.

Correct Answer: B

Rationale: The correct answer is B: 'Purified.' Aseptic means free from contamination or sterile. While 'Sterilized' (choice A) is related to the elimination of all microorganisms, aseptic goes beyond sterilization to ensure freedom from contamination in a broader sense. 'Contaminated' (choice C) and 'Polluted' (choice D) are incorrect as they mean the opposite of aseptic, implying the presence of unwanted or harmful substances.

Correct Answer: B

Rationale: The term 'Impaired' means diminished or lacking usual quality. This choice is correct as it accurately reflects the meaning of the word. Choices A, C, and D are incorrect. Choice A, 'Increased capability,' is the opposite of impaired. Choice C, 'Hyperactive,' refers to excessive activity rather than a lack of usual quality. Choice D, 'Stronger than usual,' does not capture the meaning of impaired.