Some experts warn that global warming will reduce food

Less hopeful Experts: Food production will decrease due to global warming.
More hopeful experts: Not really!! Food production will decrease only slightly because the rainfall pattern won't change much.

Thus, hopeful experts think that the change in rainfall pattern is the only factor responsible for better/worse food yield.

D is just a restatement of this assumption.

Ans: "D"

The 2nd statement of the argument -little reason to expect altered rain distribution even with warmer temperatures,leaves a reasoning gap in the argument.

Thus supporter answer choice is required.

D negating this clearly crashes the basis mentioned above. Hence an OA.

Could anybody please negate option D for me and show me how negated D shatters the conclusion

A can be a strengthening statement - yet it is not an assumption.

No that is not correct. In that case option D would read something like: Flood or storm (or high temperature or some other reason) would not cause change in food production. However what option D states is entirely different. It is a very clear case of inference (that too a faulty inference) - what type of inference it is is explained in my post above.

Yup. D is correct. The more hopeful ones claim food production only change only minimally because if minimal altered rain distribution.

Therefore it is assumed that if a warmer period is followed by change in rainfall, it would be more damaging.

Hope that helps.

Nice question. Got tricked. Now understand why D is the correct answer though. Thanks.

D as it states the statement only

I have concern with this question... i think answer has to be A rather than D
X says Food production would be affected.
Y says Food production would not be affected (conclusion), because one (K) of the two factors (K and M) is not changing much.
how can we make conclusion less believable..negation of that condition will be the assumption
what if technology (M) also not able to work then definitely the production will be affected.
now think if technology itself is powerful to save the production...
so basically K and M are the factors ... k is not changing anything so it has to be M , which is affecting the yeild

Thanks, agree A can be strengthening statement. SO what possibly be the answer

D is the correct answer

Conclusion: Warming trends wont effect food production
Premise: Little reason to believe that rain distribution would be affected by warming

Argument is trying to say that since rain distribution stays unaffected because of global warming, food production would be untouched. The argument is trying to hinge the reason - rain distribution, as a deciding factor that might have affected food production.

Possible assumptions:
- There are NO other reason apart from 'rain distribution', that affects food production
- 'Rain distribution' is necessary to be affected along with global warming for affecting food production (an extension of 1st assumption)

A is out because - it talks about improved yields.
Rest options are OFS

Try negating - it would then probably be clear why D is not an assumption.

Suppose, the experts assume that the warming trend would NOT be more damaging if accompanied by a change in rainfall patterns. With this assumption their claim that food production will change only minimally still holds. If negating D proved the claim that that food production would change drastically then D could be an assumption.

Now why D is an inference:
1. Food production would not change
2. BECAUSE the rainfall pattern would not change.

The word "because" indicates that if rainfall changes then, then the food production changes. This is an inference from the above 2 facts.

(PS: Strictly speaking even the last statement CANNOT be inferred.

Premise: If A then B.
Conclusion: If not B then not A

Premise: If not A then not B
Conclusion: If B, then A.

Option D falls in the second category of logic structure.

So the correct inference would have been:
If the food production changes , rainfall pattern must have changed.

This looks like a defender assumption to me. The argument only relates the global warming with the rain distribution. What about other adverse phenomenon (e.g., flood, storm,...)? We don't know. So it seems that the argument only talks about (one of) the most damaging impacts (aka. altered rain distribution) to food production.

That's something D says. Very subtle IMO!

everything but C and D can be eliminated.
D is better suited.
D must be the answer.

Can't find any answers ;
D is like restatement. Inference.
with POE eliminated all. A just strengthens .

Some experts warn that global warming will reduce food production. Others are more hopeful, claiming that food production will change only minimally because there is little reason to expect altered rain distribution even with warmer temperatures. In the case of most crops, annual fluctuation in rainfall and increased use of agricultural technology mask the changes in yield that are due to temperature change.

The claims of the more hopeful experts are based on which of the following assumptions?

A. Technology is so influential that regardless of climate, improved yields are likely.
Technology is out of scope for this argument
B. Climate changes cannot be predicted with accuracy.
The accuracy of the climate change is very broad term while we are discussing a very specific opints and therefore this point will not a valid point.
C. Temperature trends are more predictable than rainfall trends.
Since the rainfall treds is what matters the most for the yield of the crops this point is exact opposite of what we must be looking for.
D. The warming trend would be more damaging if accompanied by a change in rainfall patterns.
Correct answer because there is little change in the rainfall patters. and rainfall patterns are what alter the yields of the crops.
E. Cooling trends threaten food production more than warming trends.
Cooling trends are out of scope of the question.

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