One of your Systems Administrators has defined the following NACL’s rules for a subnet.
A rule is added to the security group for allowing incoming traffic on port 80 from anywhere to the EC2 Instance. Which of the following is TRUE based on the above settings?

Answer options:

A.A request from a workstation on the Internet with IP address 52.10.1.2 will be allowed onto the EC2 Instance on port 80.
B.All traffic on all ports will be denied flow into the subnet.
C.There will be an error in setting the rules for the Security Group rules due to the clash in rules.
D.All traffic out of the subnet will be denied.

Correct Answer: B
In the above screenshot, Rule number 100 will be evaluated first. Hence all traffic will be denied into the subnet.
Option A is incorrect since, by default, Rule 100 will be evaluated first. Hence all traffic will be denied into the subnet.
Option C is incorrect since the settings for the NACL and the Security Groups are separate.
Option D is incorrect since we don’t know the Outbound rules to decide on this statement.
For more information on Network Access Control Lists, please refer to the below URL-
https://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_ACLs.html