Answer:
Marginal utility of each becomes negative
Step-by-step explanation:
Utility is defined as the level of satisfaction that a person gets from consuming a product.
The person keeps on consuming the item until the level of marginal utility for the product becomes less than zero.
That is there is no satisfaction anymore in consuming the product.
In the given instance Thomas will continue to consume both candy bars and ice cream until the level of satisfaction (marginal utility) is now less than zero or negative