Explanation:

- Usher: A person responsible for showing people their seats, especially in a theater or at an event. This role involves guiding individuals to their designated places.

- Guard: A person who watches or protects a place or people, ensuring safety and security. They are not responsible for seating arrangements.

- Watchman: A person employed to keep watch or guard over a building at night, focusing on security rather than assisting with seating.

- Cameraman: A person who operates a camera for film or television. Their job is related to capturing visuals, not seating people.

Correct Answer: Usher