根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
As we all know, the spine (脊柱) stands at the center of your health, providing your body with structure and support. It also contains your spine cord, a massive collection of nerves conveying electric signals from the rest of your body to your brain. 36 .
Maintaining good posture is one of the most important things you can do to keep your spine healthy. Proper posture means standing or sitting while keeping your spine straight, except for its natural curves. Posture comes into play even when you are asleep. Sleeping on your side puts less stress on your spine than most other positions. 37 . Especially if you work at a desk most of the day, it’s important to get up and stretch regularly.
38 . Stretch can help the muscles around your spine relax and allow bones to shift into better arrangement. Strength exercises like push-ups (俯卧撑) can also help by strengthening the muscles around your spine. However, don’t overdo the exercise, as repeated movements can strain the muscles around your spine.
Finally, your diet affects the health of your spine because many vitamins are necessary for bones and nerves. In particular, vitamins B and D are essential to keep bones healthy, so you may want to consider taking a supplement. 39 , so it is also helpful to do some of the back exercise outside.
Many of the actions necessary to keep your spine healthy are identical to those used to preserve your health in other ways. 40 .
A. It can be hard on your back to stay still for too long
B. So, to have a healthy spine, you should take the following factors into account
C. Try the following exercises to keep your spine more flexible
D. So protect your back, the rest of the body will benefit
E. Exercise is also an important factor in your spine’s health
F. Doing yoga to protect your spine is also a necessary step
G. However, the latter can also be absorbed from sunlight
