A．Because nearly 1,000 million acres of land was burned off.

B．Because natural resources are being used up.

C．Because animals and plants are in danger of extinction.

D．Because natural beauty of the land would be ruined.

《本草纲目》共分16部60类，以部为纲，以类为目。每一种药又以正名、余名为目。这个纲目分类法已经具有与现代科学双名法相同的性质，有的科学史家将之与林标的分类法相提并论。