Company XYZ has a fixed price contract to produce 10,000 widgets for a price of $100,000. An invoice will not be generated until all widgets are completed. The budgeted cost of manufacturing the widgets is $9 per widget. All widgets were to be completed by today. Unfortunately, the project is behind schedule, and only 9,000 widgets have been completed. Actual manufacturing costs to date are $90,000. In the sample scenario above, what is the cost performance index ？（）
A．1.23.
B．0.9.
C．1.
D．1.1.