Answer:
A.
Step-by-step explanation:
According to researchers, babies have the ability to mimic and exaggerate the facial expressions of others. Researchers say that babies are able to mimic because of mirror neurons.
In the given case, Rosalie, who is mimicking her mother's expressions will frown, fuss, drool or look away when Mary makes a blank face. Rose will behave in such a manner because Mary's face is showing no expressions and she have nothing to mimic or exaggerate now.
So, the correct answer is option A.