For each blank, choose the best answer from the four choices and write down on the answer sheet.
Web browser is simply a terminal emulator, designed to display text on a screen. The two essential differences between an ordinary terminal emulator and a Web browser are that the browser knows how to deal with (71) , and that it has a mechanism for (72) graphical files. Display text, display graphics, and (73) hyperlinks—there’s 99 percent of the (74) value. That’s not to say that the manufacturers didn’t go all-out to attach a hyperactive efflorescence of useless capabilities onto their browsers. Remember when media channels in the browser were a big deal, instead of the clutter you can’t wait to delete from your favorites of bookmarks menu Remember when client-side Java applets were supposed to become the preferred (75) for application development Remember frames and all their nasty side effects

A．direct

B．navigate

C．indicate

D．go-on

管道工程按材料性质分，可分为（）管道。