Critical Reasoning

Plant scientists have been able to genetically engineer vegetable seeds
to produce crops that are highly resistant to insect damage. Although
these seeds currently cost more than conventional seeds, their cost is
likely to decline. Moreover, farmers planting them can use far less pesticide,
and most consumers prefer vegetables grown with less pesticide,
therefore, for crops for which these seeds can be developed, their use
is likely to become the norm.
which of the following would be most useful to know in evaluating the
argument above?
A. Whether plant scientists have developed insect-resistant seeds
For every crop that is currently grown commercially
B. Whether farmers typically use agricultural pesticides in larger
Amounts than is necessary to prevent crop damage.
C. Whether plants grown from the new genetically engineered seeds
Can be kept completely free of insect damage.
D. Whether seeds genetically engineered to produce insect-resistant
crops generate significantly lower per acre crop yields than do
currently used seeds.
E. Whether most varieties of crops currently grown commercially have
Greater natural resistance to insect damage than did similar varieties
in the past.
Answer: d

here the main problem I faced was I was unable to understand what is the conclusion .
whether it is that cost of the crop is likely to decline , or it the conclusion is that the use of geneticlly engineered crops is going to become a norm .

For such questions I usually convert the ans into a yes or no question and I check if it weakens or strenghtens the argument ...but was unable to fid the argument itself

Thanks for ur understanding
Neha