单项选择题
A. The optimizer uses a new plan because none of the plans in the exhibit2 are fixed plans.
B. The optimizer uses the plan in the second row of the exhibit2 because it is an accepted plan.
C. The optimizer uses the plan in the first row of the exhibit2 because it is the latest generated plan.
D. The optimizer uses the plan in the first row of the exhibit2 because OPTIMIZER_MODE was set to FIRST_ROW during its creation.