Well first off, this is a mathematics question. Nevertheless the answer is 1 out of 1 are defective.
It would be dangerous to give away any personal information on the internet because someone could attempt to find you, your family, your friends, your co-workers, etc. It is also important to use the internet responsibly because your future employers can track down your internet usage to see if you are worthy of the position they are offering. If those policies were broken at school you can not only get into trouble but damage your reputation to the school administrators who will be asked for recommendations for work opportunities in the future.
I can't help you, there are know answers for me to see and I'm not sure if this is a full question.
I believe it is D i hope i have helped