The Headline on the Xerox Ad Declared, "You Can't Xerox

The headline on the Xerox ad declared, "You can't Xerox a Xerox on a Xerox." Why would Xerox use its valuable advertising dollars to run such an ad in The Wall Street Journal?

A) to get business people to buy more copying machines
B) to help keep the brand name Xerox from becoming generic
C) to create name recognition
D) to show the company's high level of social responsibility
E) to show that large corporations can have a sense of humor