<prompt> Clasp assemblies that accommodate functional prosthesis movement are designed to address the concern of:Class I leverClass II leverClass III leverClass IV lever  <response>: Clasps Designed to Accommodate Functional MovementClasp assemblies that accommodate functional prosthesis movement are designed to address the concern of a Class I lever. The concern is that the distal extension acts as a long effort arm across the distal rest fulcrum to cause the clasp tip resistance arm to engage the tooth undercut. This results in harmful tipping or torquing of the tooth, which is greater with stiff clasps and increased denture base movement. Two strategies may be adopted to change the fulcrum location and subsequently the resistance arm engaging effect mesial rest concept clasp assemblies, or to minimize the effect of the lever through the use of a flexible arm wrought-wire retentive arm.Key Concept:Clasp assemblies that accommodate functional prosthesis movement are designed to address the concern of a Class I lever. Ref: McCrackens REMOVABLE PARTIAL PROSTHODONTICS, THIRTEENTH EDITION page no 72 