题目

Nowadays China (know) for its new four great inventions—shared bicycles, electronic payment, high-speed railways and onlineshopping. 答案：【1】is known关于O2的叙述①O2可以用作燃料；②O2可使带火星的木条复燃；③O2可使澄清石灰水变浑浊；④红磷在O2中自燃；⑤白磷可以在O2中自燃．其中正确的是A.①②B.②⑤C.③④D.③⑤