Final answer:
The key to re-open the last accessed record at a master file prompt can vary, but often the F5 key is used to refresh and possibly reopen the last accessed record. It is important to consult the specific application's documentation for the correct function.
Step-by-step explanation:
The keyboard key that allows you to re-open the last accessed record at a master file prompt is typically specific to the software application being used. However, commonly in many applications, the F5 key is used to refresh the current window or context, which in some cases can mean re-opening the last accessed record.
It's important to note that this can vary between different programs and operating systems, and it sometimes might be F3, F4, or F6. To get the correct answer, you would need to refer to the documentation for the specific application you're using or the context in which you're working.