Suppose a Firm's Total Cost Curve Is Given by the Equation

Multiple Choice

Suppose a firm's total cost curve is given by the equation $T C = Q ^ { 2 } + 2 Q + 100$ . The firm's marginal cost is $M C = 2 Q + 2$ . At what level of $Q$ does the firm's average cost curve reach a minimum?

A) 100
B) 2
C) 10
D) 20