<prompt> True about vertebral artery -A branch of thyrocervical trunkEnters skull through foramen magnumUnite to form posterior cerebral arteryA small artery  <response>: Ans. is b i.e., Enters skull through foramen magnum Vertebral arteryo It is the largest branch of subclavian artery.o Vertebra artery traverses through vertebral triangle, foramina transversaria of upper six cervical vertebrae. suboccipital triangle, posterior atlanto-occipital membrane, vertebral canal, pierce duramater and arachnoid Subarachnoid and passes through foramen magnum to enter posterior cranial fossa. It gives following branches:-Cervical branches Spinal branches, muscular branches to suboccipital muscle.Cranial branches Posterior inferior cerebellar artery, medullary artery, meningeal branches, anterior spinal artery, posterior spinal artery and both vertebral arteries unite to form basilar artery. 