If the circle $x^2+y^2+8x-4y+c=0$ touches the circle $x^2 +y^2+2x+4y-11=0$ externally and cuts the circle $x^2+y^2-6x+8y+k=0$ orthogonally then $k=$

Question

\[\begin {array} {1 1} (a)\;59 & \quad (b)\;-59 \\ (c)\;19 & \quad (d)\;-19 \end {array}\]