Consider the relation R = {E, F, G, H, I, J, K, L, M, N) and the set of functional dependencies F = {{E, F)-G, F-{I, J}, {E, H}^{K, L), K-ML-N). What is the key for R? Select one: O a. {E, F) O b. {E, F, H} O c. {E, F, H, K, L) O d. {E}