A knowlEDgE oF thE Composition oF thE wEED Community ______.
A．is EssEntiAl to thE EFFiCiEnt Control oF wEEDs
B．mAy lEAD us to BE AwArE oF thE FACt thAt thE soil ContAins Enormous quAntitiEs oF sEEDs oF numErous spECiEs
C．hElps us to hAvE A gooD iDEA oF why sEEDs CAn liE DormAnt For yEArs
D．proviDEs us with thE mEAns to iDEntiFy wEEDs At thE sEEDling stAgE