Kale has more nutritional value than spinach. But since collard greens

A good strategy is to set up a little diagram, in which you position the different vegetables.

Kale > Spinach Collard Greens > Lettuce

Conclusion: Kale > Lettuce

We can go through each answer choice and see which one does not reinforce the diagram above.

Starting with (A) we can see that if collard greens have more nutritional value than kale, then there is no way we can determine whether kale is healthier than lettuce:

Collard Greens > Lettuce > Kale
Collard Greens > Kale > Lettuce

Either scenario is valid. However, the first scenario goes against the conclusion and is therefore the answer.

Hope that helps .
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Kale has more nutritional value than spinach. But since collard greens have more nutritional value than lettuce, if follows that kale has more nutritional value than lettuce.
Any of the following, if introduced into the argument as an additional premise, makes the argument above logically correct EXCEPT:

Let K = Kale
S = Spinach
C = Collard
L = lettuce
Given :
1) K >S
2)C>L
Conclusion
3)K>L

A. Collard greens have more nutritional value than kale
The choice says : C >K ... (a)
From (1) , (2) and (a)
C>L
C>K>S
From this we can't conclude that C>K. This may be true, may not be true. We don't know. Hence (A) can't be the additinal premise. Hence (A) is the answer.
B. Spinach has more nutritional value than lettuce
The choice says : S > L .... (b)
From (1) and (b)
K>S>L
Hence K>L ... which is the conclusion. Hence this choice can be the additional premise.
C. Spinach has more nutritional value than collard greens
The choice says : S > C ....(c)
From (1) , (2)and ( c)
K>S>C>L
Hence K>L ... which is the conclusion. Hence this choice can be the additional premise.
D. Spinach and collard greens have the same nutritional value
The choice says : S = C ....(d)
From (1) , (2)and ( d)
K>S=C>L
Hence K>L ... which is the conclusion. Hence this choice can be the additional premise.
E. Kale and collard greens have the same nutritional value
The choice says : K=C ....(e)
From (2)and ( e)
K=C>L
Hence K>L ... which is the conclusion. Hence this choice can be the additional premise.

+++++++++++++++

Also , refer to kale-has-more-nutritional-value-than-spinach-but-since-12458.html?hilit=Kale%20has%20more%20nutritional%20value%20than%20spinach.%20But%20since

Answer A. Time to solve: 30 sec
K>S and C>L --> K>L so K must be > C
A) Says C>K --> Wrong

Kale - K
Spinach - S
Collard Greens - C
Lettuce - L

Given K > S. Since C > L, thus K > L.
For the last if then case, to be true, either K > C or/and L > S.
So, anything that goes against the above rules is the coorect AO.
A says K < C. No need to check further or make an attempt to eliminate other options! A is correct.

A is the correct answer.

Premise 1 - K>S
Premise 2 - C>L
Assumption 1- S>L
Assumption 2- S>C
Assumption 3- S=C
Assumption 4- K=C
Except- C>K

Read the question carefully. The word "EXCEPT" is very important to note. If you skip the last word then you might fall into the trap.

Once you have made a note of this word "EXCEPT" then it is easy to understand that all the 4 options (B-E) satisfy the conditions given in stimulus "EXCEPT" option A.

Hence Option A is the correct ans.
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Official Explanation:-

Argument Construction

Situation Using the symbol > to mean “has (or have) more nutritional value than,” this statement can be expressed as kale > spinach, and collard greens > lettuce. The conclusion that kale > lettuce remains valid if all but one of the premises is added.

Reasoning Which premise makes the conclusion incorrect? The information given in the passage is that kale > spinach and that collard greens > lettuce. This is not enough to conclude that kale > lettuce; another premise is needed to establish the relative nutritional value of kale and lettuce. Look at each premise offered in the answers to see whether the conclusion kale > lettuce remains valid. The ranking of vegetables may change with the additional premises; the conclusion, kale > lettuce, must not change. Find the one answer that does NOT support the conclusion.

A Correct. This statement properly identifies an additional premise that would invalidate the argument. If collard greens > kale, then it is possible that lettuce > kale, because the ranking could be collard greens > lettuce > kale > spinach.

B If spinach > lettuce, then kale > lettuce because kale > spinach.

C If spinach > collard greens, then kale > lettuce because the ranking would then be kale > spinach > collard greens > lettuce.

D If spinach = collard greens, then kale > lettuce because the ranking would be kale > spinach = collard greens > lettuce.

E If kale = collard greens, then kale > lettuce because kale = collard greens > lettuce.

The correct answer is A.
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Kale has more nutritional value than spinach. (K > S)
Collard greens have more nutritional value than lettuce (CG > L)

Conclusion: Kale has more nutritional value than lettuce. (K > L)

There is no relevance of 'but'. We just get this info from the argument and this is what it concludes.
What will help establish the conclusion and what will not?

If we know that S > CG, or S > L or K > CG etc we can prove that the conclusion holds.

A. Collard greens have more nutritional value than kale
CG > K. K could still be less than or greater than L.
Does not help prove the conclusion.

Answer (A)­
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1. K> S
2. C >L

given that 3. K> L

hence only 2 possibilities
K>S>=C>L or K>C>=S>L



hence clearly A does not fit into it

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