Correct Answer: B

Rationale: The correct punctuation needed in the sentence is a comma. The sentence should be: 'Follow my lead, I have been performing this procedure for years.' The comma is necessary to separate the introductory phrase 'Follow my lead' from the main clause that follows. The other choices are incorrect because a period would create two separate sentences, an exclamation point is not suitable for the context, and a semicolon would be too strong of a punctuation mark for this sentence structure.

Correct Answer: A

Rationale: The correct sentence is 'Because she was uncertain of her abilities, Renee asked for help.' This sentence uses a comma after the introductory phrase 'Because she was uncertain of her abilities' to set it off from the main clause 'Renee asked for help.' The comma helps to separate the two parts of the sentence clearly and indicates the pause that should be there when reading it aloud. Options B, C, and D are incorrect because they either use a semicolon incorrectly or have commas placed incorrectly within the sentence.

Correct Answer: C

Rationale: The correct punctuation needed in the sentence is a question mark. The sentence is a question, asking whether the lab results have been read in order to schedule an appointment. Therefore, a question mark is needed at the end of the sentence to indicate that it is an inquiry. The period is used for statements, not questions. A comma would not be appropriate here as the sentence is not a list or a compound sentence. An exclamation mark would imply excitement or surprise, which is not the tone of the sentence.

Correct Answer: B

Rationale: The correct pronouns to use as objects of the verb 'told' are 'her' and 'me.' Therefore, the grammatically correct sentence is: 'Dr. Chu told her and me to take a break for lunch.' 'Her' is used as the object form of 'she,' and 'me' is the object form of 'I' in this context. Choice A is incorrect because 'me' should come before 'her' in the sentence. Choice C is a duplicate of the correct answer. Choice D is incorrect because 'she' should be 'her' and 'I' should be 'me' to function as objects in the sentence.

Correct Answer: D

Rationale: The phrase 'standing with the refrigerator door open' is misplaced in the sentence as it disrupts the flow. It seems to modify 'shelf,' but it actually relates to the subject's action. Placing it after 'orange juice' would enhance clarity and conciseness. Choice A, 'I did not see,' is the introductory part of the sentence and is correctly placed. Choices B and C, 'of orange juice' and 'on the shelf,' provide necessary information and are correctly positioned in relation to the main subject and verb.