The exponential smoothing forecast for period t + 1 is a weighted average of the

a. actual value in period t + 1 with weight α and the forecast for period t with weight 1 – α.
b. forecast value in period t – 1 with weight α and the forecast for period t with weight 1 – α.
c. actual value in period t with weight α and the forecast for period t with weight 1 – α.
d. forecast value in period t with weight α and the actual value for period t with weight 1 – α.