Explanation
According to the Palo Alto Networks documentation1, the shared device group is a special device group that contains policies and objects that apply to all firewalls managed by Panorama. The policies in the shared device group can be configured as pre-rules or post-rules, which determine their priority relative to the policies in other device groups. Pre-rules have higher priority than the policies in other device groups, while post-rules have lower priority. Therefore, to ensure that a Security policy has the highest priority, the administrator should configure it in the shared device group as a pre-rule. Therefore, the correct answer is D.
The other options are not relevant or effective for ensuring that a Security policy has the highest priority:
Add the policy to the target device group and apply a master device to the device group: This option would add the policy to a specific device group, which is a subset of firewalls managed by Panorama.
The policy would only apply to the firewalls in that device group, not to all firewalls. Moreover, applying a master device to the device group does not affect the priority of the policy, but only allows synchronizing configuration changes across devices in the same device group2.
Reference the targeted device's templates in the target device group: This option would reference the templates that contain network and device settings for the targeted devices in the target device group. It does not affect the Security policy or its priority, but only allows applying consistent configuration settings across devices in the same device group Clone the security policy and add it to the other device groups: This option would create copies of the security policy and add them to different device groups. However, this would not ensure that the policy has the highest priority, because it would still depend on whether it is configured as a pre-rule or a post-rule within each device group. Moreover,this option would create redundant and potentially conflicting policies across different device groups.
References: 1:
https://docs.paloaltonetworks.com/panorama/9-1/panorama-admin/panorama-overview/centralized-firewall-conf
2:
https://docs.paloaltonetworks.com/panorama/9-1/panorama-admin/panorama-overview/centralized-firewall-conf
3:
https://docs.paloaltonetworks.com/panorama/9-1/panorama-admin/panorama-overview/centralized-firewall-conf

Explanation
https://docs.paloaltonetworks.com/panorama/10-2/panorama-admin/panorama-overview/panorama-models Management Only mode is the only Panorama mode that allows all logs to be sent to and only stored in Cortex Data Lake. In this mode, Panorama does not store any logs locally and only acts as a management interface for the firewalls and Cortex Data Lake. The other modes either store some logs locally (Legacy and Log Collector) or do not support Cortex Data Lake (Panorama).

Explanation
To provide the same level of access as the current VPN solution, which is to secure only Internet egress for the connected clients, you can configure mobile users with trust-to-untrust Security policy rules to allow the desired traffic outbound to the Internet. This way, the mobile users will be assigned an IP address from a pool that belongs to the trust zone, and they will be able to access the Internet through Prisma Access using a gateway that belongs to the untrust zone1. You do not need to configure a service connection for this scenario, as a service connection is used to enable access between mobile users and remote networks or private apps2
. You also do not need to configure trust-to-trust Security policy rules, as they are used to enable access between mobile users and other trusted resources3. References: 1:
https://docs.paloaltonetworks.com/prisma/prisma-access/prisma-access-panorama-admin/prepare-the-prisma-acc
2:
https://docs.paloaltonetworks.com/prisma/prisma-access/prisma-access-cloud-managed-admin/prisma-access-ser
3:
https://docs.paloaltonetworks.com/prisma/prisma-access/prisma-access-cloud-managed-admin/prisma-access-mo