Final answer:
The purpose of the cat-camel exercise for a client with excessive posterior pelvic tilt is to improve pelvic stability.
Step-by-step explanation:
The purpose of the cat-camel exercise for a client with excessive posterior pelvic tilt is to improve pelvic stability. Excessive posterior pelvic tilt can cause an imbalance in the muscles around the pelvis, leading to lower back pain and poor posture. The cat-camel exercise helps to stretch and strengthen the muscles of the core and lower back, promoting proper alignment of the pelvis and improving pelvic stability.