DOM is a platform-and language-____(66)___API that allows programs and scripts to dynamically access and update the content, structure and style of WWW documents ( currently,definitions for HTML and XML documents are part of the specification ).The document can be further processed and the results of that processing can be incoporporated back into the presented ___(67)____.DOM is a ___(68)___-based API to documents ,which requires the whole document to be represented in ____(69)___while processing it .A simpler alternative to DOM is the event –based SAX,which can be used to process very large ___(70)___documents that do not fit info the memory available for processing.
（68）处填（）。
A．table
B．tree
C．control
D．event