Final answer:
The correct answer is option 1 and 4. A change in consumer preferences and a change in the price of a substitute good might shift the marginal benefit curve from MB1 to MB2, by affecting the perceived value of additional units of the good or altering consumer demand.
Step-by-step explanation:
The marginal benefit curve in economics can shift due to various factors, reflecting changes in how much value consumers place on additional units of a good or service. Among the options provided, a change in consumer preferences can certainly shift the marginal benefit curve from MB1 to MB2. When consumer preferences change, the perceived value of each additional unit either increases or decreases, leading to a shift in the marginal benefit curve. A change in the price of a substitute good can also affect the marginal benefit curve since it alters consumer incentives and potentially increases or decreases demand for the original good.
However, a change in the price of the good itself, or a change in the income of consumers, would more directly shift the demand curve rather than the marginal benefit curve. Income changes alter the ability of consumers to purchase goods, and price changes directly impact the quantity demanded at each price level, thereby shifting the demand curve. These concepts are critical in understanding how markets react to changing economic circumstances.