阅读下列材料，从每题所给的A、B、C、D四个选项中选出最佳选项。
It's November. If you enjoy relaxing your mind, it's high time to go bird watching. In November, lots of visitors go to Poyang Lake of Jiangxi to relax in a special way. They watch birds. They watch white cranes(白鹤). With the coming of winter, all the birds begin to fly to some warmer places. In early November, a lot of white cranes fly across the sky of Poyang Lake.
November is not the only time to do the fun thing. In fact, in Jiangxi you can watch birds all the year round. And you can do it wherever you go. Jiangxi is a good place for birds so it has a great many birds. If you keep your eyes open, you will probably find some around you. Here is some advice for bird watching:
● Don't get too close to birds that are building nests (巢) or feeding their babies. Some birds will give up their baby birds if they are frightened.
● Take a pair of binoculars (双筒望远镜) with you so that you can see the birds more clearly.
● Buy a good field (实地) guide if you don't have one yet. It can help you know the birds that you have never seen before.
C+2MgO，以下说法错误的是（ ）