what is the best reason of using the Internet at school?这句话哪里有错

What is the best reason (for) using the Internet at school?
★ reason for sth/doing sth
例：have adequate/sufficient reason for doing sth 有充分的/足够的理由做某事
★ reason to do sth
例：We have good reason to believe that he is lying.我们有充分的理由认为他说谎.