What type of visits might be scheduled after initial requests were denied?

The correct choice emphasizes the potential for visits related to foreign entities following denied initial requests. Such visits can arise when opportunities to establish connections or gather information are pursued further, despite initial reluctance or denial. These interactions often involve personnel from foreign governments, agencies, or organizations that might seek to influence or extract information from individuals within a different country.

Understanding the dynamics of international relations and counterintelligence principles is critical in this context. After a request for a visit has been denied, foreign entities may attempt to reschedule or present themselves through different means or contacts, illustrating persistence in their objectives. This reflects a common tactic in espionage where an entity might not take 'no' for an answer and will seek to find ways around obstacles to achieve their goals.

The other options do not adequately capture how denied requests could lead to specific follow-up visits aimed at acquiring information or establishing espionage activities. Prohibited photography, last-minute visitors, and wandering visitors generally do not imply the systematic approach often employed by foreign entities in counterintelligence scenarios, making them less relevant in this context.