What Is One Possible Limitation to Using a Social Network

What is one possible limitation to using a social network in the classroom?

A) Students are familiar with this technology and are comfortable communicating and working together in this environment.
B) Students can interact and continue learning beyond the allotted seat time designated to the class.
C) Social networking may include other forms of media such as videos and podcasts.
D) Many schools restrict access to social networking sites within the building setting,which may mean that even if you create an educational application,you may not be able to use it with your students.