You want to track and store all transactional changes to a table over its lifetime. To accomplish this task, you enabled Flashback Data Archive with the retention of 5 years. After some time, the business requirement changed and you are asked to change the retention period from 5 years to 3 years. To accomplish this, you issued the following command: ALTER FLASHBACK ARCHIVE fla1 MODIFY RETENTION 3 YEARS; What is the outcome of this command?（）

A. The command produces an error because the retention period cannot be reduced

B. ll historical data older than 3 years is purged from the flashback archive FLA1

C. ll historical data is retained but the subsequent flashback data archives are maintained for only 3 years

D. ll historical data is transferred to flashback logs and the flashback archive is refreshed to set a new retention time