Katie Developed Her Corporation's Intra Net Site Using Proprietary HTML

Multiple Choice

Katie developed her corporation's intra net site using proprietary HTML language extensions based on the company's current browser. The company has recently updated its systems to include the use of a new browser. Now the intra net site that Katie developed no longer renders its content consistently. What should Katie do to ensure that this site's content renders consistently regardless of the browser used?

A) Revise the site to include workarounds and hacks for the new browser.
B) Revise the site's markup language in only those areas that are not rendering properly.
C) Update the site using a single language standard consistently, such as HTML5 or XHTML.
D) Update the site using the proprietary language extensions required by the new browser's rendering engine.