An organization needs to implement a security rule that allows users to access "Facebook" but...

Comprehensive and Detailed 150 to 250 words of Explanation From Palo Alto Networks Network Security Analyst Knowledge:

The power of App-ID lies in its ability to distinguish between different functions within the same web service. Palo Alto Networks provides specific App-IDs for various sub-functions of popular sites.

To achieve the requirement, the analyst should create two security rules (or one rule with a specific exclusion). The first rule, placed higher in the policy, would block the Facebook-chat App-ID. The second rule, placed below it, would allow the Facebook-base App-ID. Because the firewall evaluates rules from the top down, any attempt to use the chat function will hit the block rule first. This provides much higher security and granularity than URL Filtering (Option A), which might struggle to differentiate between the different elements of a dynamic, HTTPS-based site like Facebook. Using App-ID for this purpose ensures that the business can allow the useful parts of social media while mitigating the risks associated with unauthorized file transfers or interactive chat functions.