Match the items of List-I with the items of List-II and choose the correct answer.

List-I	List-II
a. Mean forecast error	1. Mean of absolute deviations of forecast demands from actual demand values
b. Mean absolute deviation	2. Mean of the squares of the deviations of forecast demands from actual demand values
c. Mean square error	3. Mean of the deviations of the forecast demands from actual demand
d. Mean absolute percent error	4. Mean of the percent deviations of the forecast demands from the actual demand