Which of the Following Statements Is (Are) True

Multiple Choice

Which of the following statements is (are) true?

A) Consumers are constrained by a budget.
B) If a consumer decides to spend more on one good, he or she must decide to spend less on another good to satisfy the budget constraint.
C) The marginal decision rule states that an activity should be expanded if its marginal benefit exceeds its marginal cost.
D) All of the above statements are true.