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If a precedence graph for a schedule is acyclic, then
Aa topological sort of the nodes gives a serial schedule equivalent to it
Bno two transactions touch the same data item
Cthe schedule has zero conflicts
Dthe schedule must commit transactions in their start order
Answer & Solution
Correct answer: A. a topological sort of the nodes gives a serial schedule equivalent to it
Acyclic = topological-sort-able. The topological order is a valid serial order whose conflicts agree with the original schedule, so it's conflict equivalent. There may be multiple valid topological orders; any one suffices. The other options confuse acyclic with no-conflict or impose unrelated commit-order constraints.
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