Final answer:
In family therapy, it is not appropriate to focus most of the session on the most dysfunctional member of the family, as effective therapy involves treating the family as an interactive and collective unit.
Step-by-step explanation:
The question addresses the practices in family therapy, which is intended to support families in resolving issues and improving their interpersonal dynamics. An inappropriate part of family therapy mentioned in the options is C. Focusing most of the session on the most dysfunctional member of the family. This approach is not appropriate as it can stigmatize and isolate that individual, which is counterproductive to the inclusive nature of family therapy, where all family members' perspectives and behaviors are considered collectively and interactively. Effective family therapy involves exploration of beliefs (A. Exploring family members' beliefs about the meanings of their behaviors), reframing behaviors positively (B. Reframing problematic behaviors positively), encouraging new interactions (D. Encouraging family members to interact differently and observe the effects), and suggesting activities or thought practices outside of sessions (E. Giving the family members things to think about and work on outside of sessions).