In Artemia, managers of large orchards are planning to import a leaf-eating moth and release it in their orchards to curb the growth of an exceptionally troublesome weed. Owners of small farms, however, rely on the weed to crowd out other weeds from temporarily uncultivated fields, since the other weeds are more difficult to eliminate once established. Therefore, the moth cannot be released in orchards without causing hardships for owners of small farms.
Which of the following, if true, most seriously weakens the argument given?
D) In exchange for government permission to import the moth, orchard growers must agree to regularly spray farms near their orchards with a long-lasting spray that repels the moth.
E) None of the other weeds that grow in Artemia cause any damage to orchard trees.
Why is the ans D and not E?