【单选题】

By saying"...owners of well over half of all World Wide Web sites have set up home with out fitting locks to their doors" (Line 3-4, Para.2), the author means that______.
A．those happy times appear still to be with us

B．there simply wasn't any crime to worry about
C．many sites are not well-protected
D．hackers try out tricks on an Internet site without actually breaking in