Which sentence is not correct?

A. “hypertext” means “a way of joining a word or image to another page, document, etc. on the Internet or in another computer program so that you can move from one to the other easily”

B. Berners-Lee had begun working with hypertext in the early 1980s.

C. An early prototype implementation of the Web became operational at CERN in 1989.

D. The idea slowly spread to universities in the rest of the world.