Create separate Network Security Groups (NSGs) for each tier and configure ingress and egress rules to restrict traffic accordingly. Configure the route table for the Web Tier subnet to route traffic destined for the Database Tier subnet through the Application Tier.

Create a single Network Security Group (NSG) and associate it with all three subnets. Configure ingress and egress rules within the single NSG to restrict traffic accordingly.

Create separate security lists for each subnet and configure ingress and egress rules to restrict traffic accordingly. Create appropriate route rules in each subnet’s route table.

Create separate security lists for each subnet and configure ingress and egress rules to restrict traffic accordingly. Configure the route table for the Web Tier subnet to route traffic destined for the Database Tier subnet through the Application Tier.