First you should select which audit you wish to remove by clicking on the drop-down
box and then clicking on the correct audit. 
i.e. If audit 4 is currently displayed, 4 will be removed leaving you with audit 3 as the most recent.
First you should select which audit you wish to remove by clicking on the drop-down
box and then clicking on the correct audit.
Then click on the Delete Audit button and you will be prompted to confirm whether you actually want to delete the audit. There will be an extra warning if the selected audit is the most recent.
This option can be used to 'roll backwards' if a significant error has been made in audit 4. So much so that it would be easier to remove audit 4 and re-create it from audit 3 than to directly correct the information.