Structure: Ok should appear if everything is ok, i.e., no primary partition between two extended partitions, one or no bootable partitions, no partitions using the same disk space.
When you are satisfied with the edited partition table, press Enter. If you've made any edits, TestDisk gives you a choice of writing that data to the drive's partition table, or of running a more detailed analysis.
Quit
Quits (exits) from the TestDisk program without making any changes (unless you pressed the ENTER key while Write was highlighted).
Write
Writes the changes that have been made in TestDisk's memory buffer to the hard drive. If you are unsure of the changes (often to the MBR's partition table), then don't use this function!