Final answer:
The 'Ready to Promote checkbox' indicates that a User Story is ready for deployment, implying it has passed necessary reviews and preparations for the production or staging environments.
Step-by-step explanation:
The Ready to Promote checkbox is a feature often found in Agile project management tools and is used for User Stories within a development cycle. The correct statement regarding this checkbox is 'c. It indicates that the User Story is ready for deployment'. This means that the User Story has been completed, reviewed, and is awaiting to be moved to the next stage in the process, which is often the production or staging environment depending on the team's workflow. It doesn't automatically get checked when a User Story is created, it is not mandatory for every User Story, and checking it does not trigger the immediate promotion of the User Story; these actions usually require manual intervention.