Which of the following should the administrator have done FIRST before migrating this server?

After an administrator successfully migrated the last physical application server to a virtual environment, the help desk reported slow performance .

Which of the following should the administrator have done FIRST before migrating this server?
A . Apply operating system patches to the application server after the migration.
B . Contact the vendor to see if the application is supported in a virtual environment.
C . Take a backup of the application server after the migration.
D . Migrate the application server in a test environment and have users test it.

Answer: B