The Computer Fraud and Abuse Act (CFAA) primarily addresses unauthorized access to computer systems and data. Among the options you've provided, the act would protect against:
a teenager illegally downloading a song
This is because the CFAA deals with unauthorized access or actions involving computers and could be applied to scenarios involving unauthorized downloads, depending on the specifics of the case.
The other options do not directly relate to the CFAA:
- Accessing a bank account legally (even from another state) doesn't involve unauthorized access.
- Advertising online to children under 13 is regulated by the Children's Online Privacy Protection Act (COPPA), not the CFAA.
- Posting negative comments on social media does not involve unauthorized access to a computer system.