Answer: Law of Demand.
Step-by-step explanation:
Law of demand states that as the price of a commodity increases, as a result demand for that commodity decreases and as the price of a commodity decreases, as a result demand for that commodity increases. This shows that there is a inverse relationship between the price and demand of a commodity.
Lower prices increase the marginal utility per dollar spent because lower price increases the purchasing of a consumer and hence increases the satisfaction level.
It is a different of restating law of demand in terms MU.