A web application requires a minimum of six Amazon Elastic Compute Cloud (EC2) instances running at all times. You are tasked to deploy the application to three availability zones in the EU Ireland region (eu-west-la, eu-west-Ib, and eu- west-Ic). It is required that the system is fault-tolerant up to the loss of one Availability Zone. Which of the following setup is the most cost-effective
solution which also maintains the fault-tolerance of your
system?
A. 6 instances in eu-west-la, 6 instances in eu-west-lb, and 6
instances in eu-west-Ic
B. 3 instances in eu-west-la, 3 instances in eu-west-lb, and 3
instances in eu-west-lc
C. 6 instances in eu-west-la, 6 instances in eu-west-lb, and no
instances in eu-west-lc
D. 2 instances in eu-west-la, 2 instances in eu-west-lb, and 2
instances in eu-west-lc