A relation can have, Only one candidate key, At most two candidate keys, Multiple candidate keys, No candidate keys, Which of the following is true about a candidate key?, It may contain redundant attributes, It must uniquely identify tuples, It must uniquely identify tuplesIt can contain duplicate valuesIt can contain duplicate values, It must always be a single attribute, R(A, B, C, D) , A → B, B → C, C → D Which attribute is a candidate key?, A, B

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