Oliver is about to complete an eight-week social skills group program led by the school social worker. When asked to recount his positive experiences of being involved in the group, Oliver becomes emotional and hesitates to speak. In which of the following stages of group development is this behavior most likely to occur?​

A) ​The separation stage
B) ​The power and control stage
C) ​The intimacy stage
D) ​The differentiation stage