Scientists have steadily increased the amount of grain that farms can produce each year. The yield for farms in France is given by y=−2.73x^2+11000x−11000000 where x is the year and y is the grain yield in kilograms per hectare (kg/ha). What does the y-intercept of this function represent?

A. the increase in crop yield every year
B. the crop yield in year zero
C. the crop yield for a given year
D. the crop yield in 1960