There __________ some men waiting for help, but the reason for their difficulties __________ unclear.

A. is; seems
B. is; seem
C. are; seems
D. are; seem

C

Perfect.

Oh, there are definitely some men waiting for help, but the reason for their difficulties seems unclear, my friend. So, I'd go with option C - "are; seems."

The correct answer is C. are; seems.

Explanation: In this sentence, the subject is "some men," which is plural. Therefore, the verb should be "are." Additionally, the phrase "the reason for their difficulties" serves as the subject complement, which means it should agree with the subject "some men" and also use the plural form "seem." So, the correct sentence structure is "There are some men waiting for help, but the reason for their difficulties seems unclear."

To find the correct answer, we need to consider the subject-verb agreement in the sentence. In this sentence, the subject is "men," which is plural. When the subject is plural, we use the plural form of the verb.

Now, let's examine the options:

A. is; seems - The verb "is" is singular, which does not agree with the plural subject "men." Therefore, this option is incorrect.

B. is; seem - The verb "is" is singular, while the plural subject "men" requires the plural form "seem." So, this option is also incorrect.

C. are; seems - The verb "are" is plural, which agrees with the plural subject "men." However, the verb "seems" is singular, which does not agree with the plural subject. Therefore, this option is incorrect.

D. are; seem - The plural verb "are" agrees with the plural subject "men," and the plural verb "seem" also agrees with the plural subject. Therefore, this option is correct.

Hence, the correct answer is D. are; seem.