“How could you have the heart to put your own child out among strangers?”
Adverb is a word or phrase that modifies the meaning of a word, and can be used to help expressing manner, feeling, place and time etc.
Though this does not apply in every situation, but adverbs are often found to end with “ly”.
In this case, foolishly is the adverb in the sentence.
Hope it helps!
Which character from the ramayana is an incarnation of the god vishnu?
rama