<prompt> Radiological factors indicating an unstable pelvis are all exceptPosterior sacroiliac complex displacement by 1 cmAvulsion fracture of sacral or ischial end of the sacrospinous ligamentAvulsion fractures of the L5 transverse processIsolated disruption of pubic symphysis with pubic diastasis of 2 cm.  <response>: ref : maheswari 9th ed 