please help

Which of the following is true concerning the smoothing constant (@) used in exponential smoothing? (Note: Use the formula R. = 4 +all - a)A,-1 + a(1 -a)?A,-2+ a(1 -a) At-3+ ... The higher the value of a, the higher the probability of forecast error. The higher the value of a, the lower the weight placed on recent periods. The higher the value of a, the higher the weight placed on recent periods. The higher the value of a, the lower the probability of forecast error. None of the above