Identity Awareness is a feature that enables the Security Gateway to identify users and groups behind IP addresses, and apply security policies based on their identity12. Identity Awareness uses different methods to acquire identities, such as AD Query, Identity Collector, and Browser-Based Authentication12. To debug Identity Awareness issues, you need to use the command pdp debug on the gateway, where pdp stands for Policy Decision Point, the component that handles the identity acquisition and enforcement13. The command pdp debug has different flags for different identity sources, such as adlog for AD Query, ic for Identity Collector, and nac for Browser-Based Authentication13. The flag extended enables more detailed debug output13. Therefore, the correct command to debug the problem of users not being able to browse internet sites with Identity Awareness using AD Query, Identity Collector, and Browser-Based Authentication is pdp debug nac extended on the gateway13. The other options are incorrect because they either use the wrong command (ad debug instead of pdp debug), the wrong flag (ad query instead of nac), or the wrong location (on the management instead of on the gateway). References:
* 1: CCTE Courseware, Module 9: Advanced Identity Awareness Troubleshooting, Slide 4
* 2: Check Point R81 Identity Awareness Administration Guide, Chapter 1: Introduction to Identity Awareness, Page 7
* 3: Check Point R81 Identity Awareness Administration Guide, Chapter 5: Troubleshooting Identity Awareness, Page 49

To troubleshoot Identity Awareness issues related to user identification and Access Role application, you need to enable debugging for both Identity Collectors (IDC) and Identity Providers (IDP). The command pdp debug set IDC all IDP all on the gateway achieves this.
Here's why this is the correct answer and why the others are not:
A . on the gateway: pdp debug set IDC all IDP all: This correctly enables debugging for all Identity Collectors and Identity Providers, allowing you to see detailed logs and messages related to user identification and Access Role assignment. This helps pinpoint issues with user mapping, authentication, or authorization.
B . on the gateway: pdp debug set AD all and IDC all: This command only enables debugging for Active Directory (AD) as an Identity Provider and all Identity Collectors. It might miss issues related to other Identity Providers if they are in use.
C . on the management: pdp debug on IDC all: This command has two issues. First, it should be executed on the gateway, not the management server, as the gateway is responsible for user identification and policy enforcement. Second, it only enables debugging for Identity Collectors, not Identity Providers.
D . on the management: pdp debug set all: While this command might seem to enable debugging for everything, it's not specific enough for Identity Awareness troubleshooting. It might generate excessive logs unrelated to the issue and make it harder to find the relevant information.
Check Point Troubleshooting Reference:
Check Point Identity Awareness Administration Guide: This guide provides detailed information about Identity Awareness components, configuration, and troubleshooting.
Check Point sk113963: This article explains how to troubleshoot Identity Awareness issues using debug commands and logs.
Check Point R81.20 Security Administration Guide: This guide covers general troubleshooting and debugging techniques, including the use of pdp debug commands.