The points (2,\minus{}3), (4,3), and (5,k/2) are on the same straight line. The value(s) of k is (are):
(A)\ 12\qquad
(B)\ \minus{}12\qquad
(C)\ \pm 12\qquad
(D)\ {12}\text{ or }{6}\qquad
(E)\ {6}\text{ or }{6\frac{2}{3}} analytic geometrygraphing linesslope