If You Burn Your Class Notes in Your Dorm Room

If you burn your class notes in your dorm room at the end of the semester in spite of regulations against it, then you are

A) acting economically irrationally and creating a social cost.
B) avoiding the private costs associated with taking your notes to the recycling and creating a social cost.
C) acting rationally and creating a positive externality.
D) saving landfill space and creating a social benefit.