Computer operating system software has become increasingly standardized. But when a large business with multiple, linked computer systems uses identical operating system software on all of its computers, a computer vandal who gains access to one computer automatically has access to the data on all the computers. Using a program known as a "virus," the vandal can then destroy much of the data on all the computers. If such a business introduced minor variations into its operating system software, unauthorized access to all the computers at the same time could be virtually eliminated. Furthermore, variations in operating system software can be created without any loss of computer compatibility to the business. Therefore, it is advisable for businesses to implement such variations.
Which one of the following, if true, supports the conclusion in the passage
A．Standardization of computer operating system software has increased computer compatibility among different businesses.
B．Correcting any damage resulting from an invasion by a computer virus program is more expensive than preventing the damage.
C．It is not costly for a business to maintain incompatible computer operating systems.
D．There are other kinds of destructive computer programs that do not depend on intercomputer links.
E．(E) Not all businesses need to share data among their internal computer systems.
