单项选择题

A.your best option would be to use the exchange management console (emc) and then select the remove option on a right-click of the -ex03 database copy on -ex01.
B.your best option would be to run clean-mail box database -identity -ex03 on the exchange management shell.
C.your best option would be to use the exchange management console (emc) and then select the manage database availability group membership on a right-click on tkdag then you can remove -ex01 from the list.
D.your best option would be to run remove-mail box database -identity -ex03\-ex01 from the exchange management shell.