What is the behavior of Defenders when the Console is unreachable during upgrades?

What is the behavior of Defenders when the Console is unreachable during upgrades?
A . Defenders continue to alert, but not enforce, using the policies and settings most recently cached before upgrading the Console.
B. Defenders will fail closed until the web-socket can be re-established.
C. Defenders will fail open until the web-socket can be re-established.
D. Defenders continue to alert and enforce using the policies and settings most recently cached before upgrading the Console.

Answer: D

Explanation:

Reference: https://docs.paloaltonetworks.com/prisma/prisma-cloud/20-09/prisma-cloud-compute-edition-admin/upgrade/upgrade_process.html