Hoffman (1981) reported that infants cry more when they hear another infant crying. he posited that this is an example of

The correct answer is empathy. 

According to Hoffman (1981) children learn empathy responses or how to empathize as part of different developmental levels or stages. Empathy is defined as a person's ability to feel the same emotions as others around them, as well as the awareness and understanding of another person's feelings. In the early stages of developing empathy, Hoffman found that infants express empathy by crying when they witness another infant crying. 

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