In a change control environment, which one of the following REDUCES the assurance of proper
changes to source programs in production status?

A.
Authorization of the change.

B.
Testing of the change.

C.
Programmer access.

D.
Documentation of the change.

Explanation:
I think I am going to disagree with the original answer (B testing of the change) here. The question
has REDUCES the assurance. “Personnel separate from the programmers should conduct this
testing.” -Ronald Krutz The CISSP PREP Guide (gold edition) pg 345