Which two items need to be taken into account to achieve a successful connection?

You have completed a rolling conversion from DNS to GNS cluster resolution from the database and
cluster resources end. The remaining are the configuration changes to be done from the client side.
Which two items need to be taken into account to achieve a successful connection?

A.
For each client using a SCAN, change the SCAN the client uses so that the client uses the SCAN in
the domain delegated to GNS.

B.
For each client using VIP names, change the VIP name on each client so that they use the same
server VIP name, but with the domain name in the domain delegated to GNS.

C.
There is no need to change anything in client configuration as the combination of TAF and ONS
will automatically take care of reaching the correct nodes.

D.
All the nodes in the cluster need to be bounced one after the other in order for the changes to be
completed as it is not possible to do it online.

Explanation:
For each client using a SCAN, change the SCAN that the client uses so that the client uses the SCAN in
the domain delegated to GNS. For each client using VIP names, change the VIP name on each client
so that they use the same server VIP name, but with the domain name in the domain delegated to
GNS.

https://docs.oracle.com/database/121/CWADD/admin.htm#CWADD92605