You are trying to connect to your instance from the internet and get an error message Network error: Connection timed out or Error connecting to [instance], reason: -> Connection timed out: connect.
Which of the below are valid checkpoints to diagnose the error. Choose 2 answers from the options given below

Answer options:

A.Check the Inbound Security Group Rules
B.Check the route table for the VPC
C.Check if a private IP address has been assigned to the instance
D.Check if the instance has been assigned a private DNS name

Answer - A and B
The AWS documentation mentions the following for troubleshooting EC2 Instance connectivity
1. Check your security group rules. You need a security group rule that allows inbound traffic from your public IPv4 address on the proper port.
2. Check the route table for the subnet. You need a route that sends all traffic destined outside the VPC to the internet gateway for the VPC.For more information on troubleshooting EC2 Instances please see the below link:
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/TroubleshootingInstancesConnecting.html