What.s the author.s opinion in part one?

A、
Teenagers. idleness and ignorance will produce serious effect on all concerned and

for society as a whole.

B、
Teenagers. idleness and ignorance will produce positive effect on all concerned and

for society as a whole.

C、
Teenagers. idleness and ignorance won.t produce any serious effect at all.

D、
Teenagers. idleness and ignorance will produce serious effect only on

themselves.