FTP sites carry a security risk because:

O

A. they are used by multiple people.

O

B. they have file size limits.

O

C. the logins are unencrypted.

O

D. they allow you to create subfolders.

the logins are unencrypted.

Explanation:

It provides neither encryption nor tamper resistance. This means passwords are transmitted in clear and an attacker can sniff the passwords. And the attacker can also modify the traffic like injecting malware into downloads.