有成绩登记表G(SNO,CNO,SCORE),请问查询所上课程的课程号(CNO)为C1和C2的学生的学号、课程...
A. SELECT SNO,CNO,SCORE FROM G WHERE CNO=C1 AND CNO=C2
B. SELECT SNO,CNO,SCORE FROM G WHERE CNO=C1 OR CNO=C2
C. SELECT SNO,CNO,SCORE FROM G WHERE CNO=”C1” AND CNO=”C2”
D. SELECT SNO,CNO,SCORE FROM G WHERE CNO=”C1” OR CNO=”C2”