Which of the following would be the best reason for sending a single SMTP message to an address that does not exist within the target company?

A.
To gather information about internal hosts used in email treatment

B.
To verify information about the Mail administrator

C.
To gather information about procedure in place to deal with such messages

D.
To create a denial of service attack

Explanation:
The replay from the email server that states that there is no such recipient will also give you some information about the name of the email server, versions used and so on.