Which of the following can be used to restrict traffic to the subnets located in your VPC.

Answer options:

A.Security Groups
B.VPC Flow Logs
C.Network Access Control Lists
D.Subnet security groups

Answer – C
The AWS documentation mentions the following
AWS provides two features that you can use to increase security in your VPC: security groups andnetwork ACLs. Security groups control inbound and outbound traffic for your instances, and network ACLs control inbound and outbound traffic for your subnets.
For more information on VPC’s and subnets please see the below link:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Subnets.html