Question: Which of the following is the key of a relation schema R = (M, N, O, P, S, T), when R has the functional dependencies shown below? O → T S → M OS → P M → N a) MO b) MS c) OP d) OS Explanation: To determine the key of the relation schema R = ( M , N , O , P , S , T ) given the functional dependencies, we need to figure out the minimal set of attributes that can determine all the attributes of the relation. This minimal set is the candidate key . Functional Dependencies: O → T O S → M S O S → P OS M → N M Step 1: Identify which attributes can be derived From O → T , if we have O , we can determine T . From S → M , if we have S , we can determine M . From M → N , if we know M , we can determine N . From O S → P , if we know both O and S , we can determine P . Step 2: Determine the closure of attri...