PPD$-21$ recommends critical infrastructure owners and operators contribute to national critical infrastructure security and resilience efforts through a range of activities, including all of the following EXCEPT: A$.$ Perform critical infrastructure risk assessments; understand dependencies and interdependencies; and develop emergency response plans B$.$ Establish continuity plans and programs that facilitate the performance of lifeline functions during an incident C$.$ Develop and coordinate emergency response plans with appropriate Federal and SLTT government authorities D$.$ Sponsor critical infrastructure security and resilience$-$related research and development, demonstration projects, and pilot programs