Insecurely attached infants who are left my their mothers in an unfamiliar setting often will
a. hold fast in their mothers in their returnb. explore the new surroundings confidentlyc. be indifferent toward their mothers on their returnd. display little emotion any time

Insecurely attached infants who are left my their mothers in an unfamiliar setting often will Hold fast in their mothers in their return.

A. Hold fast in their mothers in their return

Explanation:

It is in the conscience of the infants to have the company of their parents no matter the place or time and do not generally like to be left alone. Moreover, the questions says, insecurely attached infants which further add up to this behavior.

The infant would not explore the surroundings due to lack of confidence in an unfamiliar setting. They would rather be uncomfortable and most probably weep the time until their mother arrives and hold fast on to them on their return.  

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