The average monthly production of a factory for the first 8 months is 2,500 units, and for the next 4 months the production was 1,200 units. The average monthly production of the year will be_____________?

The average monthly production of a factory for the first 8 months is 2,500 units, and for the next 4 months the production was 1,200 units. The average monthly production of the year will be_____________?

A. 2066.55 units
B. 5031.10 units
C. 4021.12 units
D. 3012.11 units