Question : Among A, B, C, D, E and F, who is the heaviest ? Statements: A and…

Concept: In a Data Sufficiency question that asks who holds an extreme value (here, the heaviest) among a fixed group, a statement is sufficient only when it leaves exactly one member of the group who could hold that extreme, with no ambiguity remaining.

Statement I: A and D are heavier than B, E and F, but neither A nor D is the heaviest. Since all six people have distinct weights, the only person left who could be heavier than both A and D is C. So C must be heavier than A and D, who are already heavier than B, E and F -- making C heavier than every other person. Statement I alone is therefore sufficient to identify the heaviest.

Statement II: A is heavier than D but lighter than C, giving C > A > D. This fixes C above A and D, but it gives no comparison at all between C and B, E or F. Without knowing how C compares with those three, C's position relative to the whole group is not settled, so Statement II alone is not sufficient.

Cross-check: Re-reading Statement I confirms it excludes every person except C from being heaviest (A and D are excluded explicitly, and B, E and F are excluded by being lighter than A and D), so no combination with Statement II is even needed. Statement II, taken alone, never rules out B, E or F being heavier than C, confirming it cannot work by itself.

Result: Statement I alone is sufficient while Statement II alone is not sufficient.

Why the other options are wrong:

• II alone is sufficient while I alone is not sufficient -- wrong because Statement II never compares C with B, E or F, so it cannot rule out one of them being heavier; that comparison is missing no matter how the rest of the deduction runs.

• Either I or II is sufficient -- wrong because this requires each statement to work independently, and Statement II's missing C-versus-(B, E, F) comparison means it does not stand on its own.

• Neither I nor II is sufficient -- wrong because it requires both statements to fail, but Statement II failing on its own does not mean the other statement must also fail; each one has to be checked in full before concluding neither works.