Final answer:
The charge nurse should first give positive feedback directly to the AP as personal recognition, which is an effective way to acknowledge and reinforce their contributions to client care.
Step-by-step explanation:
The optimal action a charge nurse should take first to recognize an assistive personnel's (AP) contributions to client care is A. Give positive feedback directly to the AP. Providing immediate and direct feedback is the most effective way to acknowledge the AP's hard work and to reinforce their positive behavior. After recognizing their contribution personally, further appreciation can be shown by sharing their accomplishments with others, nominating them for awards, or discussing their progress with management. However, personal recognition is a powerful motivator and should be the initial step.