The correct answer is B. Forwarding unwanted messages.
Internet etiquette, also known as netiquette, is a set of guidelines for online communication. It is important to follow netiquette to avoid offending or annoying others, and to make the online experience more enjoyable for everyone.
Forwarding unwanted messages is considered to be bad netiquette because it can be annoying and disruptive to the recipient. When you forward an email, the recipient is essentially getting a copy of the same message that you received, which can be a waste of their time. Additionally, if the message is spam or contains offensive content, forwarding it can only spread the problem.
The other options are all considered to be good netiquette. A small attachment size helps to ensure that the email is delivered quickly and without problems. Including your name at the bottom of your emails helps to identify you and makes it easier for others to contact you. Using abbreviations wisely can help to save time and space, but it is important to use abbreviations that are commonly understood and to avoid using them excessively.
In conclusion, the correct answer is B. Forwarding unwanted messages.