A farmer models the crop yield (in bushels) from adding x kilograms of fertilizer by the function Y(x)=−2x2+8x+50 for 0≤x≤5. Which of the following sets of x–values must be evaluated to determine the absolute maximum yield on this interval?
a) \{0,\,5\}
b) \{0,\,2,\,5\}
c) \{0,\,4,\,5\}
d) \{2,\,5\}