Clyne and Jeff are waiting for their breakfast while their mother pours milk into their glasses. Jeff tells Clyne that the milk will increase in volume because Clyne's glass is bigger than Jeff's glass. Clyne replies that the volume of milk will not be affected by the size of the glass. This leads to an argument between the two as to who has the bigger serving. In this case, Clyne and Jeff have mastered the concept of .
A. object permanence. B. egocentrism. C. animistic thinking. D. conservation.