Data Sufficiency — Circular Seating & Facing (All Facing Centre?) Are A, B, C, D, and E — seated around a circular table — all facing the centre? I. A sits to the left of B. B faces the centre. D and E are immediate neighbours. C sits second to the right of E. II. D sits second to the right of C. C faces the centre. Both E and A are immediate neighbours of D. B sits second to the right of A.

Difficulty: Medium

Correct Answer: Statement II alone is sufficient; Statement I alone is not sufficient.

Explanation:


Introduction / Context:
We must judge whether all five persons face the centre based on positional relations.


Given Data / Assumptions:

  • I provides one explicit facing (B faces centre) and several adjacency/relative-right statements, but the combined orientation of all five is not forced.
  • II explicitly states “C faces the centre,” supplies a full chain of relative placements, and thus constrains everyone’s orientation when those rights/lefts are interpreted with C’s facing.


Concept / Approach:
In circular seating, “left/right of” depends on facing. When at least one person’s facing is fixed, the remaining left/right relations can propagate to fix all facings.


Step-by-Step Solution:

1) Under I: with only B’s facing fixed, multiple consistent configurations exist for others (some outward possible), so I is insufficient.2) Under II: since C faces centre and all others are positioned by “second right” / “immediate neighbour” relations from C and D, the configuration collapses uniquely, yielding all facing centre.


Verification / Alternative check:
Attempting outward assignments under II breaks the given “second right” relations, showing a unique inward solution.


Why Other Options Are Wrong:
I alone cannot conclude for all; together is unnecessary if II already suffices; “either alone” is false; “even both not sufficient” is false.


Common Pitfalls:
Applying left/right without fixing facing; assuming adjacency alone fixes orientation.


Final Answer:
Statement II alone is sufficient.

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