【单项选择题】
View the following SQL statements：  <br /> Transaction T1 INSERT INTO hr.regions VALUES （5，’Pole’）；COMMIT； <br /> Transaction T2 UPDATE hr.regions SET region_name=’Poles’ WHERE region_id = 5； COMMIT； <br /> Transaction T3 UPDATE hr.regions SET region_name=’North and South Poles’ WHERE region_id = 5；  <br /> You want to back out transaction T2. <br /> Which option would you use？（）<p> View the following SQL statements：  <br /> Transaction T1 INSERT INTO hr.regions VALUES （5，’Pole’）；COMMIT； <br /> Transaction T2 UPDATE hr.regions SET region_name=’Poles’ WHERE region_id = 5； CO
A、A. It is possible，but transaction T3 also backs out.
B、B. It is possible with the NOCASCADE_FORCE option.
C、C. It is possible with the NONCONFLICT_ONLY option.
D、D. It is not possible because it has conflicts with transaction T3.
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