If q is the average sewage flow from a city of population P, the maximum
sewage flow _____.

A

$$Q = \left[\frac{(4 + \surd_{p})}{(18 + \surd_{p})}\right]q$$

B

$$Q = \left[\frac{(18 + p)}{(4 + \surd_{p})}\right]q$$

C

$$Q = \left[\frac{(18+\surd_{p})}{(4+\surd_{p})}\right]q$$

D

$$Q = \left[\frac{(5+\surd_{p})}{(15+\surd_{p})}\right]q$$