The correct answer is: C. Both ‘a’ and ‘b’
The demand curve is a graphical representation of the relationship between the price of a good and the quantity demanded of that good. It shows how much consumers are willing and able to buy at different prices.
The marginal utility curve is a graphical representation of the relationship between the marginal utility of a good and the quantity consumed of that good. It shows how much additional satisfaction a consumer gets from consuming an additional unit of a good.
The price consumption curve is a graphical representation of the relationship between the price of a good and the quantity consumed of that good. It shows how much consumers are willing and able to buy at different prices, taking into account their income and the prices of other goods.
The demand curve can be derived from the marginal utility curve and the price consumption curve. The marginal utility curve shows how much additional satisfaction a consumer gets from consuming an additional unit of a good. The price consumption curve shows how much consumers are willing and able to buy at different prices, taking into account their income and the prices of other goods.
The demand curve is downward-sloping because consumers are willing and able to buy more of a good at a lower price. This is because the marginal utility of a good declines as consumers consume more of it. At a lower price, consumers can afford to buy more of the good, and they will do so until the marginal utility of the good is equal to the price.
The demand curve can also be derived from the price consumption curve. The price consumption curve shows how much consumers are willing and able to buy at different prices, taking into account their income and the prices of other goods. The demand curve is the same as the price consumption curve, except that the price consumption curve is drawn with the price on the vertical axis and the quantity consumed on the horizontal axis.
The demand curve is a useful tool for understanding how consumers behave. It can be used to predict how consumers will respond to changes in price, income, and the prices of other goods.