Incorrect answer from the book??

For the past several years, a certain technology has been universally used to transmit information among networked computers. Lately two information transmission corporations, Troma and Egmmta, have each developed seperate systems that allowed network information transmission at rates five times faster than the current technology allows. Although the systems are similarly priced and are equally easy to use, Troma's product is likely to dominate the market, because________.

(A) Egmmta has been in the business of designing information transmission systems for several years more than Troma has.
(B) The number of small businesses that need computer networking systems is likely to triple over the next few years.
(C) It is much more likely that Egmmta's system will be expandable to meet future needs.
(D) Unlike many information transmission companies, Troma and Egmmta develop computers in addition to information transmission systems.
(E) It is easier for users of the current information transmission technology to switch to Troma's product than to Egmmta's.

My answer choice was: E.

However, the answer should be C regarding to the book. Can anyone explain this to me?

It's a Chinese book (borrowed, but never seen before), and I noticed several typo's. So maybe the answer is just incorrect.