单选题
An analyst does research about standard deviation and forecasts the following information about earnings per share (EPS):
| Scenario | Probability of Scenario | Earnings per share |
| 1 | 0.25 | $8.10 |
| 2 | 0.75 | $6.15 |
The standard deviation of earnings per share is closest to:
A. 0.51
B. 0.71
C. 0.84