Let x, y, z, a, b, c be the attributes of an entity set E. If {x}, {x, y}, {a, b}, {a, b, c}, {x, y, z} are superkeys then which of the following are the candidate keys ?

Let x, y, z, a, b, c be the attributes of an entity set E. If {x}, {x,

1.	Let x, y, z, a, b, c be the attributes of an entity set E. If {x}, {x, y}, {a, b}, {a, b, c}, {x, y, z} are superkeys then which of the following are the candidate keys ?
A.	{x, y} and {a, b}
B.	{x} and {a, b}
C.	{x, y, z} and {a, b, c}
D.	{z} and {c}
Answer» C. {x, y, z} and {a, b, c}

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Let x, y, z, a, b, c be the attributes of an entity set E. If {x}, {x, y}, {a, b}, {a, b, c}, {x, y, z} are superkeys then which of the following are the candidate keys ?

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