The correct answer is B: Ensure signals from your station are less than the uncontrolled maximum permissible exposure (MPE) limits. When evaluating RF exposure levels from your station at a neighbor's home, you must ensure signals are less than the uncontrolled maximum permissible exposure (MPE) limits. Uncontrolled exposure applies to the general public. MPE limits have two categories: controlled (for operators and people who know about the exposure) and uncontrolled (for the general public). At a neighbor's home, the people are members of the general public who don't know about or control the exposure, so uncontrolled limits apply. Uncontrolled limits are stricter (lower) than controlled limits to protect the general public. You must ensure your station's RF exposure at the neighbor's location doesn't exceed these uncontrolled MPE limits. This is a legal requirement under FCC rules.