In the equation Tt = Tit-1 + Y[(Y - Yp) / Yp]t-1 + o, a negative output gap in year t - 1 would, all things equal, ... O a. Push down inflation in period t. O b. Push down inflation in period t - 1 and in period t. O c. Have no lasting effect on inflation if y = 0. O d. Push up inflation in period t