【单选题】

Because Web servers axe platform and application (71) , they can send or request data from legacy or external applications including databases.All replies, once converted into (72) . mark-up language, can then be transmitted to a (73) .Used in this way, Intranets can (74) lower desktop support costs, easy links with legacy applications and databases and, (75) all, ease of use.

A．ciphertext
B．hypertext
C．plaintext
D．supertext