Final answer:
The incorrect e-mail marketing practice is C)to use deceptive subject lines, which can lead to emails being ignored or marked as spam, and this action violates the principles outlined in the CAN-SPAM Act.
Step-by-step explanation:
The student's question relates to best practices in e-mail marketing. Among the listed options, the wrong practice in e-mail marketing is C. to use deceptive subject lines. It is essential to craft subject lines that are informative and reflective of the content in the email, as misleading or vague subject lines can lead recipients to ignore the email, or worse, to report it as spam. Moreover, it is important to adhere to legislation such as the CAN-SPAM Act, which sets the rules for commercial email, establishes requirements for commercial messages, gives recipients the right to have you stop emailing them, and spells out tough penalties for violations.
In contrast, including your valid physical postal address (option A) is required by law, monitoring what others are doing on your behalf (option B) is part of good management practice and ensures compliance with marketing standards, and avoiding the use of misleading headers (option D) helps maintain transparency and trust with email recipients.