A system administrator wants to update a web-based application to the latest version. Which of the following procedures should the system administrator perform
FIRST?

A.
Remove all user accounts on the server

B.
Isolate the server logically on the network

C.
Block all HTTP traffic to the server

D.
Install the software in a test environment

Explanation:
We should test the new version of the application in a test/lab environment first. This way any potential issues with the new software would not affect the production
environment.
Set up a test lab on an isolated network in your organization. Do not set up your test lab in your production environment.