# If one of the lines in the pair of straight lines given by $4x^2+6xy+ky^2=0$ bisects the angle between the coordinate axes, then $k \in$

$\begin {array} {1 1} (a)\;(-2,-10) & \quad (b)\;(-2,10) \\ (c)\;(-10,2) & \quad (d)\;(2,10) \end {array}$

(c) (-10,2)