Four mixture are given below

(i) Kidney beans and chick peas

(ii) Pulses and rice

(iii) Rice flakes and corn

(iv) Potato wafers and biscuits

Which of these can be separated by the method of winnowing?

(iii) Rice flakes and corn

(iv) Potato wafers and biscuits

Winnowing is used to separate heavier and lighter components of a mixture by wind or by blowing air. Rice flakes and potato wafers are lighter substances in mixture, so these are separated from the given mixture by winnowing.