At the current production point on a nation's production possibilities frontier, the marginal benefit of a slice of pizza is 500 tacos while the marginal cost of producing a slice of pizza is 750 tacos

For the nation to produce at the point of allocative efficiency, what should be done?

The marginal benefit of a slice of pizza is less than its marginal cost. Therefore to produce at the point of allocative efficiency, less pizza and hence more tacos should be produced.