Q: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Question: What characterizes the physiological aging process of the musculoskeletal system?
Options: <1> Synovial thinning. <2> Lumbar kyphosis more pronounced. <3> Breakage of the articular surfaces. <4> Shortening of muscular latency and relaxation periods. <5> Decrease in bone connective tissue.
A:
5