Which activity should be used to call another automation process?

The activity used to call another automation process is the option that allows for modular programming by invoking a separate workflow file. This capability is represented by the "Invoke workflow file" activity, which is designed specifically for this purpose.

When you want to run an entire workflow within another workflow, this activity enables you to do so seamlessly. It allows you to pass arguments to the invoked workflow, thus facilitating data exchange between the workflows. This enhances code reusability and organization, as you can break down complex automation into smaller, manageable segments.

Using this method also improves maintainability, as changes in the invoked workflow do not require a complete overhaul of the calling workflow; only the relevant workflow is modified, keeping the overall process intact. Additionally, it supports the concept of reusing workflows across different projects, leading to more efficient automation development.

The other options serve different functions: "Open application" is used to launch an application; "Sequence" is a foundational workflow structure for organizing activities; while "Invoke activity" generally refers to invoking a specific activity, not an entire workflow. Thus, appointing "Invoke workflow file" as the correct choice aligns with the best practices in RPA design, promoting modular and reusable automation solutions.