John, a junior workflow developer, has approached you for advice on a workflow process that he is defining. He is unclear about the implications of selecting the Runnable checkbox while defining the Process Activity. What advice would you offer?（）
- A Runnable allows the workflow engine to compile the process.
- B Runnable allows the process to be included as a stand-alone subprocess.
- C Runnable allows the workflow engine to check its status during process execution.
- D Runnable allows the workflow engine to define this as a top-level process and initiate it