Marginal cost is defined as the increase in total cost resulting from an increase in:

According to the early Keynesians,

a. the money demand function was unstable; the interest elasticity of money demand was extremely high; and, as a consequence, changes in the quantity of money did not have important predictable effects on the level of economic activity. b. the money demand function was stable; the interest elasticity of money demand was low; and, as a consequence, changes in the quantity of money did not have important predictable effects on the level of economic activity. c. the money demand function was unstable; the interest elasticity of money demand was low; and, therefore, changes in the quantity of money did not have important effects on the level of economic activity. d. the money demand function was stable; the interest elasticity of money demand was high; and, therefore, changes in the quantity of money did have important effects on the level of economic activity.

Humana Hospital's price/marginal cost ratio of 2.3 is most likely to decline if

A) the number of nearby hospitals increases. B) the number of nearby hospitals decreases. C) the demand curve for hospital services shifts rightward. D) the demand curve for hospital services becomes steeper.