The work of professional sectaries is so ______  that few people like to apply for it; it demands of not      only high working efficiency bust also ______  available all the time. As a result, they are ______ great    demand.      [ ]

A. demanding; being; in  

B. demanded; being; in  

C. demanding; be; in  

D. tiring; being; of

SOX is an alternative syntax for (71) . It is useful for reading and creating XML content in a text editor. It is then easily transformed into proper XML. SOX was created because developers can spend a great deal of time with raw XML. For many of us, the popular XML (72) have not reached a point where their tree views, tables and forms can completely substitute for the underlying. (73) language. This is not surprising when one considers that developers still use a (74) view, albeit enhanced, for editing other languages such as Java. SOX uses (75) to represent the structure of an XML document, which eliminates the need for closing tags and a number of quoting devices. The result is surprisingly clear.

A．tree

B．text

C．program

D．graphic