At a physical examination, a nurse asks the father of a 4-year-old how the boy is developing socially. The father sighs deeply and explains that his son has become increasingly argumentative when playing with his regular group of three friends. The nurse recognizes that this phenomenon is most likely due to which of the following?
a) The fact that preschoolers have a harder time sharing than toddlers
b) Playing in an even-number group of children (four)
c) Testing and identification of group role
d) Regression
Answer: Testing and identification of group role