Server actions in OutSystems have what restriction when calling other actions?

In OutSystems, server actions are specifically designed to execute on the server-side, and they can only call other server actions. This architectural choice ensures that any logic running on the server is properly encapsulated and that the separation of client-side and server-side functionality is maintained.

Client actions, on the other hand, are intended for execution on the user's device and can use client-side resources like the user interface. Allowing server actions to call client actions would blur this separation and could lead to inefficient processing and potential security issues, as it would expose server-side logic to the client environment.

The other choices imply broader capabilities that server actions do not possess, such as calling client actions or being unable to call any actions at all, which misrepresents their intended functionality. Therefore, the correct understanding aligns with the principle that server actions are specifically limited to calling only server actions for effective and secure application design.