In the research performed by Tronick & Weinberg, mothers were instructed to interact with their infants by copying their babies' facial expressions, and then on cue to show no emotional reaction at all. This procedure is called the:

Still face

Explanation:

Still face as described by Tronick and Weinberg is a phenomenon in which an infant, after three minutes of “interaction” with a non-responsive expressionless mother, “rapidly sobers and grows wary.He makes repeated attempts to get the interaction into its usual reciprocal pattern. When these attempts fail, the infant withdraws orients his face and body away from his mother with a withdrawn, hopeless facial expression.”

answer; (b) ; /stronger bonds between the nations of africa

answer; the cats meowing will temporarily increase, but then it will decrease;