Final answer:
To ensure custom logic fires only via UI, it should be implemented to trigger from a UI event, isolated to prevent accidental activation, and documented for clarity for other developers. Adhering to these principles will help in maintaining the logic's integrity and intended functionality.
Step-by-step explanation:
If you wish to ensure that your custom logic only fires via a UI event, you must consider several factors to design it effectively. Firstly, A. The logic should be implemented so that it is specifically triggered by a UI event. Next, B. You should ensure the logic is well isolated within the codebase to prevent it from being activated unintentionally through other means. Finally, C. To maintain clarity and maintainability, document the logic thoroughly to communicate to other developers how it works and when it should be triggered. Considering all these aspects will help in maintaining the integrity of the custom logic and ensuring it functions as intended within the user interface context.