What is necessary for each form control that passes a value to a script?

Each form control that is designed to pass a value to a script must be mapped to a corresponding script argument. This mapping is essential because it establishes a direct link between the information captured by the form control and the script's processing logic. When a form control is mapped to a script argument, it ensures that the data entered by the user is correctly handed off to the script for further processing, analysis, or actions that may follow.

Mapping ensures that the data flow is seamless and that the intended actions based on user input are executed accurately. Without this mapping, the script would not know which data corresponds to what action, leading to potential errors or ineffective script execution. Therefore, this requirement is fundamental to enable the proper functionality of forms in the scripting environment.

In the context of the other choices, while having editable controls, default values, or descriptions may enhance user experience or clarity, they do not affect the ability of the control to transmit values effectively to the script. Mapping to script arguments is the key technical requirement for value passing.