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Que. Consider the relation scheme R = {E, F, G, H, I, J, K, L, M, M} and the set of functional dependencies {{E, F} -> {G}, {F} -> {I, J}, {E, H} -> {K, L}, K -> {M}, L -> {N} on R. What is the key for R?
a. {E, F}
b. {E, F, H}
c. {E, F, H, K, L}
d. {E}
Answer:{E, F, H}
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