The estimated demand for a good is

^

Q = 25 - 5P + 0.32M + 12Pr

where Q is the quantity demanded of the good, P is the price of the good, M is income,

and PR is the price of related good R. If the price of the good falls by $4, the quantity

demanded will ________ by ________ units.

A. increase; 50 units

B. decrease; 12 units

C. increase; 20 units

D. increase; 5 units

E. increase; 48 units