What is the purpose of a latch in a door mechanism?

A latch in a door mechanism is designed to catch and hold the door tightly against the frame, ensuring that it remains closed and secured. This function is critical for maintaining privacy and security, as it prevents the door from swinging open unintentionally. The design of the latch allows it to engage with a corresponding strike plate on the door frame, which keeps the door in a closed position while still allowing for easy closure and opening when needed.

Option A does not accurately describe the primary function of a latch, as latches do not hold doors open; that is typically the role of devices like door stops or wedges. Option C is also not the main purpose of a latch; while some locking mechanisms may provide visual indications of being locked, this is not a function of the latch itself. Lastly, option D, while related to the door’s operability, does not encapsulate the primary purpose of a latch, which is focused more on securing the door's position rather than securing the handle.