Select the option that expresses the given sentence in active voice.
The ball of yarn was being nudged by the kitten.

Correct option is C

Option (c) is the correct active voice of the given sentence.
 Active Voice- Active voice is a grammatical structure in which the subject of the sentence performs the action expressed by the verb.
 Passive Voice- Passive voice refers to a grammatical construction where the subject of a sentence undergoes an action rather than performing it. In passive voice sentences, the emphasis is on the recipient or object of the action.
Rule for changing the given sentence into active voice and vice-versa-
Object + auxiliary verb (was, were) + being + past participle + by + subject -> <- Subject + was, were + verb + ing + object.