Reasoning
Data Sufficiency
Each of the following questions consists of a question followed three statements labeled I, II and III. You have to decide whether the data given in the statement(s) is/are sufficient for answering the question. Read all the statements carefully and seek all the possible combinations which could be sufficient for answering the question. A single combination of statements with least number of statements which could be sufficient for answering the question would be your answer.
Who among A, B, C, D and E is the lightest?
I. B is lighter than A & D & heavier than E.
II. A is heavier than B and lighter than D.
III. C is heavier than B.
A  I and II only 
B  I and II only 
C  I, II and III

D  II and III only 
E  None of these

On combining all the informations we know that E is the lightest among all the five persons. But on the other hand from statements I and III also, we get the same answer. Since, we require least combinations of statements to get the answer, hence (b) is the correct choice.
Data Sufficiency Flashcard List
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