How many NSGs and network security rules should you create?

HOTSPOT
You have an Azure subscription named Sub1.
You create a virtual network that contains one subnet. On the subnet, you provision the virtual machines shown in the following table.

Currently, you have not provisioned any network security groups (NSGs).
You need to implement network security to meet the following requirements:
Allow traffic to VM4 from VM3 only.
Allow traffic from the Internet to VM1 and VM2 only.
Minimize the number of NSGs and network security rules.
How many NSGs and network security rules should you create? To answer, select the appropriate options in the answer area.
NOTE: Each correct selection is worth one point.
Hot Area:

Correct Answer:

Explanation/Reference:
Explanation:
NSGs: 2
Network security rules: 3
Not 2: You cannot specify multiple service tags or application groups) in a security rule.
References:
https://docs.microsoft.com/en-us/azure/virtual-network/security-overview