Which combination of steps should a solutions architect recommend?

A company wants lo build an immutable infrastructure for its software applications. The company wants to test the software applications before sending traffic to them. The company seeks an efficient solution that limits the effects of application bugs

Which combination of steps should a solutions architect recommend? {Select TWO)
A . Use AWS Cloud Formation to update the production infrastructure and roll back the stack if the update fails
B . Apply Amazon Route 53 weighted routing to test the staging environment and gradually increase the traffic as the tests pass
C . Apply Amazon Route 53 failover routing to test the staging environment and fail over to the production environment if the tests pass
D . Use AWS Cloud Formation with a parameter set to the staging value in a separate environment other than the production environment
E . Use AWS Cloud Formation to deploy the staging environment with a snapshot deletion policy and reuse the resources in the production environment if the tests pass

Answer: A,B