During the Apollo _______ was celebrated as "The Program That Reached the Stars" due to its success in landing humans on the moon.
Which choice completes the text so that it conforms to the conventions of Standard English?
missions, the National Aeronautics and Space Administration
missions, the National Aeronautics and Space Administration,
missions the National Aeronautics and Space Administration
missions, the National Aeronautics and Space Administration-
Correct Answer: A
Choice A is the best answer. "During the Apollo missions" is an introductory prepositional phrase. It should be followed by a comma to separate it from the main subject "the National Aeronautics and Space Administration." No punctuation is needed after the subject.
Choice B is incorrect because the comma after "Administration" separates the subject from the verb "was celebrated." Choice C is incorrect because it is missing the comma after the introductory phrase. Choice D is incorrect because the dash separates the subject from the verb.