Did not clear up transaction log after backup?

I performed a complete database backup using the backup wizard and checked
"Remove inactive entries from transaction log". After the backup was
completed, I discovered that the size of the transaction log did not go down.
How can I clear the transaction log?
Hi
BACKUP LOG file and the DBCC SHRINKFILE command ( for more details please
refer to BOL)
"joeau" <joeau@.discussions.microsoft.com> wrote in message
news:B0DF5822-6FCE-411B-8603-BD0F64E13DAD@.microsoft.com...
> I performed a complete database backup using the backup wizard and checked
> "Remove inactive entries from transaction log". After the backup was
> completed, I discovered that the size of the transaction log did not go
down.
> How can I clear the transaction log?