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單項(xiàng)選擇題

Given that tables T1 and T2 contain the following rows:
Table T1: C1 C2 1 4 1 3 1 2
Table T2: C1 C2 1 1 1 2 1 3
Which of the following queries will return only those rows that exist in both T1 and T2?()

A.SELECT * FROM t1 UNION SELECT * FROM t2
B.SELECT * FROM t1 UNION DISTINCT SELECT * FROM t2
C.SELECT * FROM t1 INTERSECT SELECT * FROM t2
D.SELECT * FROM t1 WHERE (c1,c2)= (SELECT c1,c2 FROM t2)

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