Correct Answer: A

Rationale: The correct answer is 'dog, who had.' The phrase 'dog, who had' correctly indicates that Janet called her dog to run after a squirrel. In this case, 'who had' provides additional information about the dog, making the sentence grammatically accurate. Choices B, C, and D are incorrect because they do not use the appropriate relative pronoun 'who' for referring to animals.

Correct Answer: D

Rationale: The word 'laying' is used incorrectly in the sentence. The correct word should be 'laying' when referring to the action of setting up a brick foundation. Therefore, the correct choice is 'D: laying.' In this context, 'lying' would imply being in a horizontal position, which is not the intended meaning. Choices A, B, and C are not incorrect in the sentence and do not affect the clarity or correctness of the statement.

Correct Answer: D

Rationale: The correct answer is 'which' as it correctly introduces a defining clause describing the style of hair Tracey wore. 'Which' is used to provide additional information about the noun 'French braid' and helps specify the particular style among others. 'Among' (choice A) is incorrect as it is used to show a relation of one thing to many others. 'It' (choice B) is incorrect as it does not serve as a relative pronoun to introduce a clause. 'That' (choice C) is incorrect as it is not the most suitable relative pronoun to introduce a non-restrictive clause in this context.

Correct Answer: A

Rationale: The correct answer is 'Is.' In this sentence, the subject 'picking up groceries' is singular, so it should be followed by the singular form of the verb 'to be,' which is 'is.' The verb should agree with the subject in number. 'Am' is incorrect as it is the first person singular form, 'Is it' creates an unnecessary question structure, and 'Are' is plural, not matching the singular subject. Therefore, 'Is' is needed to make the sentence grammatically correct.

Correct Answer: D

Rationale: In the sentence, 'The nurses went to the conference room,' 'nurses' is the subject. The subject of a sentence is typically the noun or pronoun that carries out the action or is described in the sentence. In this case, 'nurses' is the noun performing the action of going to the conference room. Choices A, B, and C are not the subject. 'Conference' and 'room' are objects of the prepositions 'to' and 'the,' while 'went to' is the verb phrase indicating the action performed by the subject.