GMAT Critical Reasoning (CR) | Re: Because postage rates are rising, Home Decorator magazine

I want to ask about answer E
E.Production costs for the magazine are expected to remain stable.
The question says that: magazine's profits are likely to decline if the plan is instituted
Profits = revenue - cost
To reduce profits, we need to reduce revenue or/and increase or keep costs the same.
So E potentially reduces the profits
Why is E not an answer?