Refer to the Figure

Refer to the figure.
Northwestern crows fly to 5 meters high (indicated by the arrow) to drop whelks in an effort to open and eat them. Based on the figure, crows should prefer to choose

A) large whelks, because their high caloric benefit outweighs their high cost in handling time.
B) large whelks, because they require the lowest handling time for the highest energy benefit.
C) medium whelks, because they provide the optimal balance between energy benefit and cost in handling time.
D) small whelks, because they are easiest to find and therefore have the lowest cost in search time.