Answer: Scientists found a perfectly preserved woolly mammoth frozen in ice
Explanation:
Active voice in a sentence occurs when there's a subject which acts upon its verb. On the other hand, the passive voice means that the subject is the recipient of the action of the verb.
In this case, the active voice is "Scientists found a perfectly preserved woolly mammoth frozen in ice". while the passive voice is "Perfectly preserved woolly mammoth was found frozen in ice by scientists".
