$34.$ If a banking system has ample reserves, which of the following is an action taken by the central bank that would cause a decrease in the cyclical rate of unemployment in the short run?

$($A$)$ An increase in the required reserve ratio

$($B$)$ An increase in the policy rate

$($C$)$ An increase in the discount rate

$($D$)$ A decrease in interest on reserves

$($E$)$ A decrease in personal income tax rates