Evaluate the following statement： Which statement is true regarding the evaluation of rows returned by the subquery in the INSERT statement？（）
- A They are evaluated by all the three WHEN clauses regardless of the results of the evaluation of any other WHEN clause.
- B They are evaluated by the first WHEN clause. If the condition is true， then the row would be evaluated by the subsequent WHEN clauses.
- C They are evaluated by the first WHEN clause. If the condition is false， then the row would be evaluated by the subsequent WHEN clauses.
- D The INSERT statement would give an error because the ELSE clause is not present for support in case none of the WHEN clauses are true.