The correct answer is - We were given new toothbrushes by the hygienist.
Passive voice means that the 'subject' of the sentence is undergoing some action - something is being done to it. If you look at sentence D, you will see that the hygienist is performing an action on the 'subject,' which is the pronoun <em>we. </em>The active voice of the same sentence would be - <em>The hygienist gave us new toothbrushes. </em>
The answer would be A or B because an indefinite pronoun doesn't refer to any specific person , thing or amount. Between either or us
