Answer:
Option (a) is correct.
Explanation:
A demand curve is a graphical representation of various quantity demanded allocation at a different price level and there is a inverse relationship between the price of the commodity and the quantity demanded of that commodity.
As the price of a good decreases then this will result in an increase in the quantity demanded and on the other hand, if there is an increase in the price of the commodity then as a result the quantity demanded for that commodity falls.
Therefore, this relationship of price and quantity demand construct a downward sloping demand curve.