The correct answer is: is.
The army is a singular noun, so it takes a singular verb. The verb “to be” is used to describe the state of being, and in this case, the army is in the state of going through its training.
The other options are incorrect because they are plural verbs. The verb “to have” is used to describe possession or ownership, and the verb “were” is used to describe a past event.
Here is a more detailed explanation of each option:
- A. are
The verb “to be” is used to describe the state of being. In this case, the army is in the state of going through its training. The army is a singular noun, so it takes a singular verb.
- B. have
The verb “to have” is used to describe possession or ownership. In this case, the army does not possess or own anything.
- C. is
The verb “to be” is used to describe the state of being. In this case, the army is in the state of going through its training. The army is a singular noun, so it takes a singular verb.
- D. were
The verb “were” is used to describe a past event. In this case, the army is not going through its training in the past.