Tianyu Nei answered the role of safety filtering technology, which of the following is still correct? (multiple choice)

Tianyu Nei answered the role of safety filtering technology, which of the following is still correct? (multiple choice)
A . File filtering can reduce the risk of malicious code execution and virus infection in the internal network by blocking the transmission of fixed types of files, and it can also prevent Prevent employees from leaking company confidential documents to the Internet.
B. Content filtering can prevent the disclosure of confidential information and the transmission of illegal information
C. The application behavior control function can finely control common HTTP behaviors and FTP behaviors.
D. Mail filtering refers to the management and control of mail sending and receiving, including preventing the flooding of spam and anonymous emails, and controlling the sending and receiving of illegal emails.

Answer: A,B,C,D