Which of the following protocols is related to the term open relay? 05/22/2020 – by Mod_GuideK 0 Which of the following protocols is related to the term open relay? A. SMTP B. POP3 C. NTP D. IMAP E. LDAP SHOW ANSWERSCorrect Answer: A Explanation/Reference: Download Printable PDF. VALID exam to help you PASS.