In 1980, for the first time, the number of foreigners touring the Unit

This sentence correction question is testing subject-verb agreement and clarity. Let's evaluate the answer choices:

(A) were in excess of the number of Americans
- This choice has a subject-verb agreement issue. "The number" is singular, so it should be followed by "was" instead of "were." Also, the phrase "in excess of the number of Americans" is wordy and can be expressed more concisely.

(B) had an excess over the Americans who were
- This choice has an awkward and wordy construction with "had an excess over" and "the Americans who were." It is not the most clear or concise option.

(C) exceeded the Americans who were
- This option fixes the subject-verb agreement issue and provides a clear and concise comparison. It correctly uses "exceeded" to compare the number of foreigners touring the United States with the number of Americans going abroad.

(D) numbered more than the Americans
- This choice is concise and clear. It uses "numbered more than" to compare the two groups. However, it doesn't use the word "exceeded" as in the original sentence.

(E) exceeded the number of Americans
- This option is concise and clear, using "exceeded" to make the comparison between foreigners touring the United States and the number of Americans going abroad.

Both option (C) and option (E) are grammatically correct and clear. However, option (E) is slightly more concise and is a better choice:

"In 1980, for the first time, the number of foreigners touring the United States exceeded the number of Americans going abroad."