下列关于保险分类的叙述有误的一项是( )。

A．以保险基金来源的不同划分，可分为商业保险、社会保险与政策保险
B．以被保险标的的不同性质为标准，可将商业保险分为财产保险与人寿保险
C．以保险的实施形式划分，可将保险分为自愿保险与强制保险
D．以保险人承保危险的数量为标准，可将保险分为单一危险保险与综合危险保险

When jumping into water upon which there is an oil-fire，you should（）.

A.break the water surface with your hands when diving head-first

B.use your hands to hold your knees to your chest

C.cover your eyes with one hand while pinching your nose shut and covering your mouth with the other

D.enter the water at the bow or stern on the windward side of the vessel