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What We Take from And Give to the Sea

As long as we have been on earth, we have used the sea around US. We take from the ocean, and we give to it.
We take fishes from the ocean—millions of kilograms of fish, every year, to feed millions of people. We even use their bones for fertilizer. We take minerals from the ocean. One way to get salt is to place seawater in a shallow basin and leave it until it evaporates. Along with salt, other minerals are left after evaporation. Much gold and silver drift dissolved in the waters of the sea, too. But the sea does not give them up by simple evaporation. Other gifts from the sea are pearls, sponges and seaweed. Pearls become jewelry. Natural sponges become cleaning aids. Seaweed becomes food of many kinds—even candy, and ice cream—as well as medicine. Believe it or not, flesh water is another gift from the sea. We cannot drink ocean waten Some of its contents may cause illness. But ocean water b
A. evaporation of seawater.
B. death of sea life.
C. destruction of land.
D. avoidance of pollution.