Sections of most commercial Web sites are off-limits except to subscribers and registered customers and have a(n) ____ Web page that users must go through to get to the off-limits area.

A ________ is a named collection of formatting characteristics

A) theme B) style C) template D) layout

?_____ is an effective troubleshooting tool during the development process and adds a valuable level of professionalism to one's work.

A. ?Stacking B. ?Validation C. ?Synchronization D. ?Indexing