Question

what is authentication for? a to add a password to allow users to edit pages b to allow search engine robots to spider the site c to restrict access to pages via a username and password d to provide promotional materials to search engines

Explanation:

• Option A: Authentication isn't just for editing pages; it's about access control, not only enabling editing.
• Option B: Authentication has nothing to do with search engine robots spidering a site.
• Option C: Authentication's main purpose is to restrict access to resources (like pages) by verifying identity through username and password (or other methods), so this matches.
• Option D: Authentication doesn't provide promotional materials to search engines.

Answer:

C. To restrict access to pages via a username and password