The Following Diagram Shows Emily's Demand Curves for Hot Chocolate

The following diagram shows Emily's demand curves for hot chocolate. On a normal day, Emily's demand curve for a cup of hot chocolate is shown as D. On a freezing day, her demand curve shifts rightward to D'. At a price P, Emily's consumer surplus on a freezing day: ​
Figure 6.8
​

A) cannot be determined without calculating her marginal valuation of a cup of hot chocolate.
B) increases significantly over her consumer surplus on a normal day.
C) will vary depending on whether hot chocolate is a normal or an inferior good.
D) increases only if her demand curve is unit-elastic.
E) decreases significantly over her consumer surplus on a normal day.