Answer:
The methodology that Kristen is considering to implement is:
d. Canary deployment.
Step-by-step explanation:
This deployment type creates a second production environment (better called a testing environment). Here, patches and updates are first applied for testing purposes before shifting traffic to the main production environment. In a server environment, the idea of canary deployment is to first deploy the changes to a small subset of servers, test them before rolling out the changes to the rest of the servers. It enjoys some advantages over other deployment strategies because it allows for testing.