Which two are true about Oracle Optimizer Statistics, their use, and their collection? (Choose two.)

A: The number of table rows is considered when evaluating the cost of accessing a table using an index. B: Index balanced B*Tree height is considered when evaluating the cost of using an index. C: The Statistics Advisor can help recommend the best way to gather statistics. D: Statistics collected using DBMS_STATS always yield the best optimizer result. E: The Statistics Advisor generates actions for all recommendations.