Answer:
Imitate babies' babbling
Step-by-step explanation:
The answer is --- Imitate babies' babbling.
Joseph McVicker Hunt was a famous American author and educational psychologist. He encouraged and researched concepts that is related to malleable behavior of a child intelligence.
In the Iranian orphanage, Joseph McVicker Hunt trained caretakers about the human enrichment to imitate the babies' sound or murmuring.
babbling is a stage in the young children where babies create or experiments with any articulate sounds but does not mean any recognizable words.
Thus the answer is ---
Imitate babies' babbling