In the following question, a sentence has been given in Active/Passive voice. Out of the four alternatives suggested, select the one which best expresses the same sentence in Passive/Active voice. The puppy spilled the milk as it drank.

• Spilling of the milk has been done by the puppy while drinking it.
• The milk was spilt by the puppy as it drank.
• While drinking it the puppy has spilt the milk.
• The milk was being drunk by the puppy when it was spilled.