: 错Isobel consumes positive quantities of both jam and and juice. The price of jam is 5 cents per unit and the price of juice is 10 cents per unit. Her marginal utility of jam is 10 and her marginal utility of juice is 5.A:Without changing her total expenditures, she could increase her utility by consuming more jam and less juice.B:Without changing her total expenditures, she could increase her utility by consuming more juice and less jam.C:Without changing her total expenditures on jam and juice, she could not increase her utility.D:We can’t tell whether any of the other statements are true or false without knowing the quantities she consumes.