Correct Answer: C

Rationale: The correct answer is 'C: herself.' In this sentence, 'herself' is the reflexive pronoun that correctly refers back to Mary Ann. It shows that Mary Ann is giving credit to herself for studying hard and passing the test. The use of 'oneself' (choice A) would be incorrect here as it is too general and does not specify Mary Ann. Choices B and D ('itself' and 'themselves') are also incorrect because they do not match the singular subject 'Mary Ann.' Therefore, 'herself' is the only option that fits both grammatically and contextually in this sentence.

Correct Answer: A

Rationale: The word 'her' is the best substitute for the underlined words 'the nurse' in the sentence. This substitution avoids redundancy and provides clarity by referring back to the nurse as a third-person singular pronoun, maintaining coherence and avoiding ambiguity. 'He' (choice B) and 'his' (choice C) are incorrect as they do not align with the gender of the nurse in the sentence. 'It' (choice D) is also incorrect as it does not refer appropriately to a person.

Correct Answer: C

Rationale: The correct answer is C. The sentence requires an infinitive form of the verb 'to conduct' after the verb 'promised.' This structure is commonly used in English grammar, where the main verb 'promised' is followed by an infinitive verb form. Therefore, the sentence should read: 'The students promised to conduct themselves with quiet dignity.' Choice A ('conduct') is incorrect as it is not in the infinitive form required after 'promised.' Choice B ('conducting') is incorrect as a gerund does not fit the grammatical structure of the sentence. Choice D ('to be conducted') is incorrect as it changes the meaning of the sentence, suggesting that someone else will conduct the students, rather than the students conducting themselves.

Correct Answer: A

Rationale: The word 'stealthy' is used incorrectly in the sentence. The correct adverb form of the word should be 'stealthily' to modify the verb 'moving.' Therefore, it should be 'Moving stealthily, the sneaky little boy reached for the cookie jar on the topmost shelf.' Choices B, C, and D are all used appropriately in the sentence. 'Sneaky' describes the boy, 'reached' is the action verb, and 'topmost' correctly describes the location of the cookie jar.

Correct Answer: A

Rationale: In this context, 'principle' is spelled incorrectly. The correct word should be 'principal,' which means main or primary. 'Principle' refers to a fundamental truth or belief. Choice B, 'role,' is correctly spelled. Choice C, 'provision,' is also spelled correctly. Choice D, 'convenient,' is spelled correctly as well. Therefore, the correct answer is A as it is the only word spelled incorrectly in the context of the sentence.