Solve the Problem $C(x)$ Be the Cost Function And $R(x)$ The Revenue Function

Solve the problem.
-Le t $C(x)$ be the cost function and $R(x)$ the revenue function. Compute the marginal cost, marginal revenue, and the marginal profit functions.
$C(x) =0.0003 x^{3}-0.036 x^{2}+300 x+10,000$
$R(x) =350 x$

A) $C^{\prime}(x) =0.0009 x^{2}+0.072 x+300$
$\mathrm{R}^{\prime}(\mathrm{x}) =350$
$P^{\prime}(x) =0.0009 x^{2}+0.072 x+50$
B) $C^{\prime}(x) =0.0009 x^{2}-0.072 x+300$
$\mathrm{R}^{\prime}(\mathrm{x}) =350$
$P^{\prime}(x) =0.0009 x^{2}-0.072 x-50$
C) $C^{\prime}(x) =0.0009 x^{2}-0.072 x+300$
$\mathrm{R}^{\prime}(\mathrm{x}) =350$
$P^{\prime}(x) =-0.0009 x^{2}+0.072 x+50$