Let R = (A, B, C, D, E, F) be a relation scheme with the following dependencies C → F, E → A, EC → D, A → B. Which of the following is a key for R ?

Let R = (A, B, C, D, E, F) be a relation scheme with the following dep

1.	Let R = (A, B, C, D, E, F) be a relation scheme with the following dependencies C → F, E → A, EC → D, A → B. Which of the following is a key for R ?
A.	CD
B.	EC
C.	AE
D.	AC
Answer» C. AE

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Let R = (A, B, C, D, E, F) be a relation scheme with the following dependencies C → F, E → A, EC → D, A → B. Which of the following is a key for R ?

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