Critical Reasoning

The drought in the central part of the country is estimated to reduce this year's national corn harvest by more than one-third from its normal levels. Such a shortfall would subsequently increase meat and other food prices by about 17% in one year and 20% in two years. So, either we spend a small amount now to irrigate the largest affected corn fields and avert severe inflation later, or else fail to irrigate now and insure inflation later.

The argument is valid only if

other American agricultural areas are also not expected to meet their anticipated corn yields this year

irrigation is the only way that the national corn yield can be significantly increased

the heat wave and drought will persist through the next two years

irrigation will insure that corn harvests reach normal levels

it is politically feasible for government authorities to spend money irrigating fields at the present time

confused b/w b and d.
but would go with d(irrigation will ensure that....)

what'S the OA?

My answer - B

yes, answer must be B.

B) Irrigation is the only way that the national corn yield can be significantly increased.
D) Irrigation will insure that corn harvests reach normal levels

Corn Harvest down by 33% => Inflation of Meat and Other food prices.
Conclusion: Irrigate -> Avert Inflation later OR
Don't Irrigate ->be ready for Inflation.

They have not mentioned actual reason why corn harvest is down. There can be many reasons like bad seeds, not having pest controls etc. So, there may be many ways we can increase the production of Corns like using pesticides, using good sophisticated seeds.
B) This says irrigation is only way corn yield can be increased and Inflation is avoided resulting. So, It eliminates any other possible ways increasing corn yield. So, It's the answer.
D) Irrigation will insure harvest reach normal level. But, It is not the only way, there can be any other way 'X' which will also insure the same. So, this option got eliminated.