<prompt> Structure crossing dorsal surface of ischial spine are AE :Internal pudendal vesselPudendal nerveObturator nerveNerve to obturator internus  <response>: C. i.e. Obturator nervePsoas major, iliacus pectineus muscles, femoral vessels and nerve, femoral branch of genitofemoral nerve, lateral cutaneous nerve of thigh and lymphatics pass below inguinal ligament.PIN structures i.e. Pudendal nerve, Internal Pudendal vessels, Nerve to obturator internus come out of greater sciatic foramen, cross the dorsal surface of ischial spine enter into lesser sciatic foramen. 