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The recurrence T(n) = 2T(n/2) + 2 with T(1) = c solves by iteration to

AO(log n)
BO(n log n)
CO(n)
DO(n²)
Answer & Solution
Correct answer: C. O(n)
Unrolling k = log₂ n levels: T(n) = 2^k · T(1) + 2(2^k - 1). With 2^k = n, this is O(n). The min-max divide-and-conquer algorithm hits exactly this recurrence; the work doubles at each level but the per-level constant is small, so the dominant term is the bottom recursion which is O(n).
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