Final answer:
The athlete who exercises regularly is most likely to have the highest bone density due to the positive impact of weight-bearing and resistance exercises on bone tissue deposition.
Step-by-step explanation:
Among the options given, c) An athlete who exercises on a regular basis is most likely to have a higher bone density. This is because regular exercise, particularly weight-bearing and resistance exercises, are key factors in stimulating the deposition of more bone tissue. Weight-bearing exercises include activities like weight training, dancing, stair climbing, running, and hiking, all of which put stress on the bones and stimulate bone building. Conversely, sedentary lifestyles can lead to a decrease in bone density over time.
Additionally, nutrition plays a vital role in bone health, and including foods high in calcium and vitamin D in the diet is essential for building and maintaining strong bones. While it is important for adolescents to consume enough calcium during their years of peak bone mass development, regular exercise remains a critical aspect throughout life to maintain bone density and prevent conditions such as osteoporosis.
While drinking milk may contribute to a teenager's calcium intake, and walking can be beneficial for bone health, regular resistance exercise has a more pronounced effect on bone density. Therefore, the athlete who regularly engages in such activities is likely to have the most robust bone health amongst the given options.