An Important Thing to Remember About the Reach of the Internet

An important thing to remember about the reach of the Internet as an IBP medium is that

A) its reach varies dramatically, based on ever-changing levels of Internet traffic.
B) only about half of U.S.households have access, so reach is quite limited.
C) its reach seems large, but it doesn't allow for access to geographically diverse locations.
D) after TV and radio, no other medium has comparable reach.