19. Suppose $f ( x ) = ( x + 1 ) ^ { 2 }$ for $x \geq - 1$ If $g ( x )$ is the function whose graph is reflection of the graph of $f ( x )$ with respect to the line $y = x$ then $g ( x )$ equals\\
(A) $\quad - \sqrt { } x - 1 , x \geq 0$\\
(B) $\quad 1 / ( x + 1 ) ^ { 2 } , x > - 1$\\
(C) $\quad \sqrt { } ( x + 1 ) , x \geq - 1$\\
(D) $\quad \sqrt { } \mathrm { x } - 1 , \mathrm { x } \geq 0$\\