The Profit Function for a Certain Company Making and Selling $x$

Multiple Choice

The profit function for a certain company making and selling $x$ units of a product is given by $P ( x ) = - x ^ { 2 } + 16.37 x + 52.44$ . Find the smallest value of $x$ at which the company breaks even.

A) $4.37$
B) $\quad 4.21$
C) $\quad 5.21$
D) $\quad 4.69$
E) $\quad 4.94$