Which of the following is a standard guideline for business emails? a. always include a clear subject line. b. write in all caps if the message is important. c. never write an email with just a few paragraphs. d. expressing emotions, such as humor, is encouraged.

A. 
In a business setting, employees are often receiving many e-mails every day. Each e-mail that is sent should contain a clear subject line, because it may not otherwise be addressed as quickly as e-mails that do, and/or important information may not be received. 

For Example, "Please Read for Today's Meeting" would likely get read before, and is more clear than, "No Subject".

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