Final answer:
The scenario B where the school counselor has a part-time family practice and sees students and parents from the district is the riskiest in terms of creating a dual relationship with ethical implications.
Step-by-step explanation:
The situation that has the greatest risk of creating a dual relationship that could ethically impact the relationship between a professional school counselor and a student is B. The school counselor has a part-time family practice and counsels parents and students within the school district. This scenario creates an inherent conflict of interest and risks confidentiality issues, as the counselor may inadvertently share sensitive information across different roles. Moreover, the counselor's ability to remain neutral and objective could be compromised when working with students and their families in multiple contexts, potentially affecting their professional judgment within the school setting.