Consider the following economy. C = 1000 + 0.8YD T = 0.25Y 1 = 325 G = 225 X = 450 M = 0.1Y If investment increases to 425, equilibrium GDP... O a. Decreases because the multiplier is negative. O b. Increases by 2125. O c. Increases by 850. O d. Increases by 200