If Everyone in an Economy Buys and Sells Goods at Market-Wide

Multiple Choice

If everyone in an economy buys and sells goods at market-wide prices:

A) people will pay the same prices, so everyone's marginal rate of substitution will be the same.
B) people will pay the same prices, but will have different marginal rates of substitution.
C) people will pay different prices, but will have the same marginal rates of substitution.
D) people will pay different prices and therefore will have different marginal rates of substitution.