SMTP protocol works on which port number?

A. 80

B. 143

C. 110

D. 25

Correct Answer is :

D. 25

Explanation

SMTP (Simple Mail Transfer Protocol) is used for sending emails.

The default port for SMTP is 25.

Other commonly used SMTP ports:

• 587 → Secure email submission (modern standard)
• 465 → SMTPS (older secure method)