A Solutions Architect is designing a web application that uses Amazon CloudFront, an Elastic Load Balancing Application Load Balancer, and an Auto Scaling group...

A Solutions Architect is designing a web application that uses Amazon CloudFront, an Elastic Load Balancing Application Load Balancer, and an Auto Scaling group of Amazon EC2 instances. The load balancer and EC2 instances are in the US West (Oregon) region. It has been decided that encryption in transit is necessary by using a customer-branded domain name from the client to CloudFront and from CloudFront to the load balancer.
Assuming that AWS Certificate Manager is used, how many certificates will need to be generated?