Why not c

We would diagram this question as Sell below MP -> discount -> high sales -> Mass tastes or specialized market The question stem is telling us that they dont cater to mass tastes so we could effectively revise our conditional chain as Sell below MP -> discount -> high sales -> specialized market. C is saying if no access to a specialized market then no discount. And that definitely could be true - it matches our conditional chain. Having a specialized market is a necessary condition for high sales, which is a necessary condition for a discount. If we fail to have a specialized market, then, we will fail to have a discount. Remember the question is asking CANNOT be true, and C could be true, so it's wrong. Hope this helps!