The correct options are
A Winnowing is the process of separating grain from chaff.
C Threshing is loosening of grain from chaff.
∙ Grain can be separated from chaff by a method called winnowing. In its simplest form, it involves throwing the mixture into air so that the wind carries away the light chaff, while the heavier grains fall down for recovery. There is no loss of fodder in the process of winnowing. Since it is done manually it is time-consuming.
∙ The process of loosening grains or seeds from husk is called threshing. It is done before winnowing. Modern equipment used for threshing may cause fodder loss.