Newborns are born with innate sensory abilities that they do not have to learn; however, one way they learn about their environment is via the method first identified by pavlov.

The answer that best completes the statement above is CLASSICAL CONDITIONING. Classical conditioning is actually proposed by Ivan Pavlov and this is even known as the Pavlovian conditioning. When we say classical conditioning, one learns via potent stimulus and this stimulus is being paired with a previous stimulus that is neutral. 

Dropping a dry bar of soap on the ground won’t clean it, by it will pick up germs from the ground so the soap would be dirty