单选题 An analyst does research about financial leverage and gathers the following information about a company:

Units produced and sold in 2010	150000
Degree of operating leverage at 150000 units	2.5
Degree of financial leverage	2.0
Expected growth rate of unit sales in 2011	10%

The expected change in operating income for 2011 is closest to:
A. 20%.
B. 25%.
C. 50%.