Refer to the exhibit.

A client can roam successfully between AP1 and AP2. However, the client is unable to roam
between AP2 and AP3. What could be the problem?

A.
The client is not using RSN+802.1X authentication mode.

B.
The AP2 and AP3 are not in the same mobility group.

C.
The network is using IPv6.

D.
The IACTP service has been disabled on AC1.