<prompt> In a vertex presentation the diameter of engagement is:SuboccipitobregmaticSuboccipito-frontalOccipitofrontalBitemporal  <response>: Ans. A. SuboccipitobregmaticFetal skulla. Mento vertical diameter 14.5cm,b. Submentovertical 11.5cm,c. Sub occipitofrontal 10cm,d. Suboccipitobregmatic 9.5cm diameter of engagement in vertex presentation,e. Biparietal 9.5cm. 