Reference:
https://docs.microsoft.com/en-us/azure/virtual-network/network-security-groups-overview

Explanation

Box 1: B1
B1 (Basic) would minimize cost compared P1v2 (premium) and S1 (standard).
Box 2: Cross Origin Resource Sharing (CORS)
Once you set the CORS rules for the service, then a properly authenticated request made against the service from a different domain will be evaluated to determine whether it is allowed according to the rules you have specified.
Note: CORS (Cross Origin Resource Sharing) is an HTTP feature that enables a web application running under one domain to access resources in another domain. In order to reduce the possibility of cross-site scripting attacks, all modern web browsers implement a security restriction known as same-origin policy. This prevents a web page from calling APIs in a different domain. CORS provides a secure way to allow one origin (the origin domain) to call APIs in another origin.
References:
https://azure.microsoft.com/en-us/pricing/details/app-service/windows/
https://docs.microsoft.com/en-us/azure/cdn/cdn-cors

Statement 1: Yes
Vnet1 and Vnet3 are peers.
Statement 2: No
Statement 3: No
Peering connections are non-transitive.
References:
https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/hybrid-networking/hub-spoke

Explanation/Reference:
https://docs.microsoft.com/en-us/azure/azure-monitor/log-query/search-queries
https://docs.microsoft.com/en-us/azure/azure-monitor/log-query/get-started-portal

Azure container networking plugin : Correct Choice
With the Azure container networking plugin , every pod gets an IP address allocated.
With Azure CNI, every pod gets an IP address from the subnet and can be accessed directly. These IP addresses must be unique across your network space, and must be planned in advance. Each node has a configuration parameter for the maximum number of pods that it supports. The equivalent number of IP addresses per node are then reserved up front for that node. This approach requires more planning, as can otherwise lead to IP address exhaustion or the need to rebuild clusters in a larger subnet as your application demands grow.
Nodes use the Azure Container Networking Interface (CNI) Kubernetes plugin.
Kubenet : Incorrect Choice
The kubenet networking option is the default configuration for AKS cluster creation. With kubenet, nodes get an IP address from the Azure virtual network subnet. Pods receive an IP address from a logically different address space to the Azure virtual network subnet of the nodes.
Service Endpoints : Incorrect Choice
Capabilities like service endpoints or UDRs are supported with both kubenet and Azure CNI, the support policies for AKS define what changes you can make. For example:
* If you manually create the virtual network resources for an AKS cluster, you're supported when configuring your own UDRs or service endpoints.
* If the Azure platform automatically creates the virtual network resources for your AKS cluster, it isn't supported to manually change those AKS-managed resources to configure your own UDRs or service endpoints.
Network security groups : Incorrect Choice
A network security group filters traffic for VMs, such as the AKS nodes. As you create Services, such as a LoadBalancer, the Azure platform automatically configures any network security group rules that are needed.
Reference:
https://docs.microsoft.com/en-us/azure/aks/concepts-network