单项选择题
A.Input.GetMouseButtonDown(0)B.Input.GetMouseButtonDown(1)C.Input.GetMouseButtonDown(2)D.Input.GetMouseButtonDown(-1)
A.Input.GetKey (KeyCode.D)B.Input.GetKeyDown(KeyCode.D)C.Input.GetKeyUp(KeyCode.D)D.Input.GetKeyDown(KeyCode D)