Let $f ( x , y ) = x y + 3$

Multiple Choice

Let $f ( x , y ) = x y + 3$ . Then $f ( x + \Delta x , y ) - f ( x , y )$ is

A) $\Delta x + 3 \Delta y$
B) $y - \Delta x$
C) $y + \Delta x$
D) $y \Delta x$
E) $\Delta x \Delta y$