Official Explanation:-
Argument ConstructionSituation 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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