Final answer:
Wearing sensible shoes to prevent ankle sprains is the best understanding of how the aging process affects the musculoskeletal system.
Step-by-step explanation:
The statement that shows the best understanding of how the aging process affects the musculoskeletal system is 'I wear sensible shoes so I won't sprain an ankle.' As we age, our bones lose mass and become brittle, which makes them more prone to fractures. Wearing sensible shoes can help prevent ankle sprains by providing proper support and stability to the feet and ankles.