<prompt> Which of the following is not required for retention of cast gold restoration?Cavosurface bevelParallel wallsBeveled axiopulpal line angleUndermining dentinal walls  <response>: Retention form is attained byCreating a maximum of 2-degree occlusal divergence of the vertical walls,Accentuating some line angles, andExtending the lingual surface groove to create an axial wall height in this extension of at least 2.5 mm occlusogingivally.Sturdevant Operative Dentistry 7th edition page e110 