What is the best practice a consultant should recommend to the admin?

Cloud Kicks has just deployed an of its configurations. The admin wants to build a separate process but uses most of the objects that were deployed.

What is the best practice a consultant should recommend to the admin?
A . Build m a test release environment and test changes in Production.
B . Build in a Developer Sandbox and test changes in Production.
C . Build in a Developer Sandbox and test changes in a test release environment.
D . Build m a testrelease environment and test changes in a test release environment.

Answer: C