How does setting up network services like DNS and FTP in a chroot environment help prevent an attacker from gaining privileged access?

A.
A chroot environment prevents buffer overflow attacks.

B.
A chroot environment prevents an attacker from initiating a reliable port scan.

C.
Programs are limited to executing in the chroot directories and not the main system directories.

D.
An attacker cannot initiate a denial of service (DoS) on the network service running in the chroot environment.