How do u get the answer

- The ounnut demand (IS) curve is given by the following equation: Y=1+r11 where r is the real interest rate and Y is current output. - The Phillips curve is given by the following equaiton: i=0.1(YYm)+0.95i where Ym is the efficient level of output and equal to 10 , and i is the anticipated (future) inflation and equal to 3%. - Assume that the nominal interest rate is set by the central bank equal to 12%. In addition, suppose the central bank has the following loss function: L=2(ii)2+(YmY)2 where i is the inflation target for the central bank and equal to 1.9%. Find the optimal monetary policy for the central bank. (Choose the closest answer.) A. The central bank must decrease the nominal interest rate to 10%. B. The central bank must decrease the nominal interest rate to 11%. C. The central bank must keep the nominal interest rate at 12%. D. The central bank must increase the nominal interest rate to 13%