"So who’s right—the mom trying to protect her kids from the perils of new technology or the dad who’s coaching his kids to embrace it? It’s an urgent question at a time when more than 80% of U.S. school districts say they are on the cusp of incorporating Web-enabled tablets into everyday curriculums."

primarily to...

a
make an emotional argument
b
establish credibility
c
establish the context
d
establish the exigence