If two variables $x, y$ are related by $ax+by+c=0$ with $ab < 0$ then correlation coefficient between $x$ and $y$ is given by

Question

$\begin {array} {1 1} (A)\;1 & \quad (B)\;-1 \\ (C)\;0 & \quad (D)\;None\: of \: these \end {array}$