A、Water and food. B、Heat and sand. C、Medicine and water. D、Plant and animals. B在西撒哈拉居住的Saharawi部落认为热和沙就是良药．故选B)。

The Sahara Desert is one of the driest regions on earth. Very little grows in temperatures that can reach 57°C. (33)So what could be healthy about this place? According to the Saharawi. a tribe who live in the desert in the Western Sahara. it has more than enough of what is needed:heat and sand.
    The Saharawi have been using the sand cure for hundreds of years. And recently this treatment has been gaining popularity with tourists. My guide explained the technique:"We make a big hole, cover ourselves in lotion . get in the hole and stay in the sun for a few hours. "
    The Saharawi believe the cure alleviates skin and back problems. And a local doctor backs up their claims. "It’s very good for your bones, muscles and circulation, " Dr Coulon says.
    So, after several cups of mint tea, I agreed to try the cure myself. At midday the heat is at its peak and you can hardly walk on the hot sand. I started wishing for a cooling wind. Bad idea. The experience of being buried in sand is not unpleasant— it’s a bit like a hot, dry bath. But the experience of having sand in your mouth is not pleasant at all.
    After 20 minutes I was so relaxed I felt I could stay there for ever. The desert is so quiet. But ten minutes later, my guides started helping me out. The Saharawis spend two hours. My conclusions? Well, (35)I certainly felt more relaxed and very clean—when I’d got all the sand out of my ears, and mouth, of course.
33. Q: According to the Saharawi, what is healthy in The Sahara Desert?
34. Q: What is the healing effect of sand?
35. Q: How did the speaker feel after he tried the sand cure himself?