Which signal confirms that a post is secure?

The correct signal that confirms a post is secure is Signal 28. This signal is specifically designated for this purpose, indicating that the post has been properly established and is stable. When a post is secure, it means that all necessary checks have been completed, and there is assurance that it will fulfill its intended function without risk of being compromised.

This confirmation is essential for operational effectiveness, as it allows other units or personnel to proceed with related tasks without needing to reassess the status of the post. The clarity of Signal 28 in identifying a secure post aids in maintaining communication among personnel and ensuring that everyone is informed about the operational conditions.