Suppose a client calls and advises you that an FTP data transaction is not allowing him to view the host??s directory structure. What are the most likely causes of the problem? (Choose all that apply.)

A.
The client??s username/password is wrong.

B.
The client??s FTP data port is not connected.

C.
The host machine has denied him access because the password is wrong.

D.
An access list is stopping port 20 from detailing the directory list.