15.Adam is a rational economic decision maker who enjoys eating ice cream from local shops. Ice cream is priced by the scoop, suchthat the marginal cost to Adam of the 3rd scoop of ice cream is $4. If Adam has chosen to eat only 2 scoops of ice cream, whichof the following statements must be true?a.Adam's marginal benefit of consuming the 3rd scoop is $4b.Adam's marginal benefit of consuming the 2nd scoop is less than or equal to $4c.Adam's marginal benefit of consuming the 3rd scoop is less than $4d.Adam's marginal benefit from consuming the 2nd scoop is greater than $4