Select the correct passive form of the given sentence.

The new owners hired a lot of new servers.

A lot of new serves were hired by the new owners.

The correct passive form of the given sentence is A lot of new servers were hired by the new owners.

The active voice of the sentence is "The new owners hired a lot of new servers." This sentence is in the simple past tense, which is used to describe an action that happened in the past. The passive voice of the sentence is formed by putting the subject of the active sentence after the verb "to be" and the past participle of the main verb. In this case, the subject of the active sentence is "servers" and the main verb is "hire." The past participle of "hire" is "hired." So, the passive form of the sentence is "A lot of new servers were hired by the new owners."

The other options are incorrect because:

• A lot of new servers are being hired by the new owners." This sentence is in the present progressive tense, which is used to describe an action that is happening now but is not finished. However, the action of hiring the new servers has already happened.
• A lot of new servers are hired by the new owners." This sentence is in the simple present tense, which is used to describe an action that happens regularly or happens now. However, the action of hiring the new servers has already happened.
• A lot of new servers had been hired by the new owners." This sentence is in the past perfect tense, which is used to describe an action that happened in the past before another action happened. However, there is no other action mentioned in the sentence.