Full Atomicity, Consistency, Isolation, Durability (ACID) compliance is a necessity for a new application, which heavily reads and writes data. This requires the following config file options: Sync_binlog=1 Innodb_flush_log_at_trx_commit=1 Innodb_doublewrite=1 However, this configuration is expected to introduce disk I/O overhead. What three changes will reduce disk I/O overheads?（）

• A、Use of soft links for database directories on the same physical disk
• B、Use of delay_key_write=ON for batch index update
• C、Allocation of RAM to the buffer pool such that more of the data can fit in RAM
• D、Placement of InnoDB log files and datadir on separate physical disks
• E、Use of separate directories on the same physical disk for log files and data files