Concept:Total cost function is the integral of marginal cost function, plus a constant determined by a given condition.Explanation:Given marginal cost MC=10+24x−3x2.Integrate to find total cost TC: ∫(10+24x−3x2)dx=10x+12x2−x3+C.Given TC=25 when x=1 (one unit): 10(1)+12(1)2−(1)3+C=2510+12−1+C=25⟹21+C=25⟹C=4.Thus, TC=10x+12x2−x3+4=4+10x+12x2−x3.Answer:Option A: 4+10x+12x2−x3