Choose the correct sentence: A. Supply curve shifts if income change. B. Demand curve shifts because of change in income. C. Demand curve has a positive slope. D. Supply curve has a negative slope.

The correct sentence is:<br /><br />B. Demand curve shifts because of change in income.<br /><br />Explanation: The demand curve can shift due to various factors, including changes in income. When income increases, it generally leads to an increase in demand for normal goods, causing the demand curve to shift to the right. Conversely, a decrease in income would shift the demand curve to the left.