--Looking for something that convinces me that these saltwater plants are a better idea than Freshwater plants.

"Different". We don't know better or worse. Can't take chances.

Okay. Thanks for letting me know but how does this help me decide if these are better than freshwater plants? Not falling for it.

This seems to be weakening the conclusion. Not good. Moving on.

Again "different". No idea if the cost is less or higher than conventional crops. Wrong.

Bingo! Stimulus told me that pumping seawater is cheaper than freshwater. This options says water is one of the biggest expenses. This means if I use saltwater, I can feed my animals at a much cheaper cost. ANSWER!

Conclusion: Agriculture in desert which is near sea level is cost-effective if we use seawater than freshwater.
Why? Because pumping seawater into farms near sea level is much cheaper than pumping freshwater from deep wells
Therefore, We are looking for a strengthener with cost aspect to it.

Which one of the following, if true, most strengthens the argument above?


We are not concerned about the nutritional value of halophytes.


Not covering the cost aspect.


This option is touching the cost aspect but research expenditures is out of scope. We are interested in the cost effectiveness of using sea water for agriculture.


This option is saying that there is difference in cost when you irrigate halophytes with sea water and when you irrigate conventional crops with sea water. It does not tell us whether this difference is good(cost effective difference) or bad(expensive) difference. Also cost of irrigation of conventional crops with sea water is out of scope.


There might be several costs involved in growing, harvesting, and distributing any forage crop(halophyte/conventional) for animal forage. But Pumping water for irrigation is one of the largest costs and pumping sea water cuts down this major cost.
Hence, sea water is cost effective.

Do we have to consider info related to desert regions?

This is a strenghtening question, so we need to try to find a gap in the argument so that one of the options can eliminate it.

Background: Researchers -> halophytes -> cost-effective
1ºCounterPremise: halophytes -> more water (not good)
1ºPremise -> halophytes -> seawater -> cheaper
2ºCounterPremise: seawater ->less yields (not good)

So we need to strenghten that halophytes are cost-effective. To do that we need an option that either eliminates the 2 counterpremises, which are not good or that finds more importante premises in favour of halophytes. One las thought before starting. Please realize that no measures are given. More water, less yields, cheaper, etc. So an option that helps us know by how much is all of this to finally conclude that indeed it is actually cost effective would be what we are looking for. Let's start

(A) A given volume of halophytes is significantly different in nutritional value for animal forage from the same volume of conventional forage crops.

Different in nutrional value, but better or worse nutrional value? It doesn't secify so this cannot be the answer. Incorrect

(B) Some halophytes not only tolerate seawater but require salt in order to thrive.

Seawater has salt so it doesn't make sense. But if it didn't require it. This is a weakness because it requires something that wasn't mention in the argument, therefore, it is more costly and therefore it is less cost/efficient. Incorrect

(C) Large research expenditures are needed to develop the strains of halophytes best suited for agricultural purposes.

research expenditure menas less cost-effective. This is a weakness. Incorrect

(D) Costs other than the costs of irrigation are different for halophytes grown by means of seawater irrigation than for conventional crops.

Again it says different, but we don't know if more or less so we can't evaluate it. Incorrect


(E) Pumping water for irrigation is proportionally one of the largest costs involved in growing, harvesting, and distributing any forage crop for animals.

Aha! this is the answer. It says tha pumping costs are the most important ones in irrigation. And the argument mentioned that pumping costs for seawater are cheaper. Therefore, this shows that halophytes are cost-effective. Correct

How's E a strengthener ? It just says that it is one of the largest costs. But there maybe other costs which are higher for seawater agriculture. Please guide.

azhrhasan , we are never told that any costs for seawater are higher than those for conventional freshwater agriculture.
Your argument is very sensible. It is realistic. But it is not supported by a single word in the prompt.

In CR and LR, stay only with the facts that are given to you.
I would avoid focusing on what you do not know and what is not mentioned in the prompt.

Try not to "import" facts that are not in the premises and conclusion.
Doing so plays right into the hands of LSAC.

Having practiced thousands of these questions and taken the LSAT with 50+ of these bad boys, I promise that this approach works: stay with the text you are given.

Sure, there may be other costs that are higher in seawater agriculture than in conventional agriculture.
We don't care about them, at all, because we know absolutely nothing about them.
We cannot be asked to evaluate something about which we know nothing.
Pretend these other theoretically high seawater agriculture costs don't exist.
They are not mentioned in the prompt and as such the conclusion does not depend on them.

We are here to find something that strengthens the (very specific) conclusion.

(E) Pumping water for irrigation is proportionally one of the largest costs involved in growing, harvesting, and distributing any forage crop for animals.

This fact supports the claim of cost-effectiveness in the conclusion.

At every stage of agriculture, pumping fresh water is proportionally one of the largest costs.
If I do this sea level desert seawater agriculture, using "much cheaper" pumped seawater, I save a lot of money at every stage of the process.
If we know (E), then we have strengthened the conclusion.
One of the proportionally largest costs just got a lot cheaper. Sounds cost-effective to me.

I hope that helps.
_________________

Strengthen question

We are given two methods to grow forage for animals: one involves seawater and the other one involves normal water.

All that we know is that pumping seawater is more cost effective than pumping normal water. From this evidence the conclusion is drawn: seawater agriculture is more cost effective than normal agriculture even tough the yields are smaller.

The argument relies on the fundamental assumption that there are no other relevant costs involved in seawater agriculture that are not involved in normal agriculture.

While all the other statements do not impact the argument option E strengthen our assumption by stating that pumping water for irrigation is the largest cost involved.