Jose goes to an all-you-can-eat buffet at a Chinese restaurant and consumes three plates of food. He does not go back for a fourth plate of food because

The marginal utility of the fourth plate is zero or below zero

Explanation:

The reason is that the law of diminishing marginal utility says that the marginal utility of a product declines upon continuous consumption of that item. This means that the utility before the consumption of first buffet was high and when the second buffet was consumed by the same person the utility was further reduced and so on. This means that the utility must be positive which if is higher enough then the customer is will to pay and eat the buffet again. If it is zero or below zero the customer is not willing to pay for the buffet. This is the reason the person doesn't ordered the item again.

You can not eat the same buffet for all the 365 days. This means the taste of a tasty food fades away after some time or I would say that the utility is gone. Same is the case when you will keep using cellphone for a period and then sell it or dispose it because the item doesn't entertains you or in other words the utility has significantly fallen and is almost zero or below zero.

the answer is "b.the increased supply will create a surplus. "

the essential thought behind price controls is straightforward - utilize the power of law to modify the equilibrium of a market. for instance, the legislature may choose that the steel business needs to survive, and in this way pass a law to set a value floor on steel. this implies all steel sold must offer at or over the floor value, which must be set over the equilibrium cost for it to have any impact. the switch could likewise happen - the administration can choose that steel is excessively costly and set a value roof underneath its equilibrium value, with the goal that all steel must be sold at or beneath that ceiling.