Answer:
Changes in the Quantity Demanded: II & III
People are buying less chicken because the price of chicken has increased.
People are buying more chicken because the price of chicken has fallen.
Explanation: The quantity of chicken sold or bought will be dependent on how much they cost at that particular time.
If they are expensive people will be buying less of chickens and the quantity that the shops will need to order will decrease.
When the price drops they will be buying more chickens and the shops will have to order more chickens the higher the demand the more supply of chickens will be needed.
Change in Demand: I
People are buying less chicken because the price of beef has fallen.