Web 2.0 sites enable user interaction, content creation, and social features. Social networking sites (B) are quintessential Web 2.0. Bank transaction sites (C) with interactive features qualify as Web 2.0. CMS platforms like Joomla/phpBB (E) enable user-generated content. Option A is static HTML - not Web 2.0. Option D is a simple Flash site - product showcase without user interaction.