# If D1, D2,...,Dn, are domains in a relational model, then the relation is a table, which is a subset of

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If D1, D2,...,Dn, are domains in a relational model, then the relation is a table, which is a subset of
1. D1 ⊕ D2 ⊕ .... ⊕ Dn
2. D1 × D2 × ...× Dn
3. D1 ∪ D2 ∪ ...∪ Dn
4. D1 ∩ D2 ∩ ...∩ Dn

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Correct Answer - Option 2 : D1 × D2 × ...× Dn

The correct answer is "option 2".

CONCEPT:

Given a set of domains D1, D2,..., Dn,

The Cartesian product DX D2 x...x Dn is set of all n-tuples(ordered) <d1,d2...dn> such that d1 ∈ D1, d2 ∈ D2, …, dn ∈ Dn.

So, the Mathematical relation on D1, D2,..., Dn is a subset of Cartesian product D1 X D2 x...x Dn.

Hence, the correct answer is "option 2".