4. The diagonals of a parallelogram PQRS are along the lines $x + 3 y = 4$ and $6 x - 2 y = 7$. Then PQRS must be a :
(A) rectangle
(B) square
(C) cyclic quadrilateral
(D) rhombus
4. The diagonals of a parallelogram PQRS are along the lines $x + 3 y = 4$ and $6 x - 2 y = 7$. Then PQRS must be a :\\
(A) rectangle\\
(B) square\\
(C) cyclic quadrilateral\\
(D) rhombus\\