| CHOICE | S | |
| CHOICE%TELESCOPE | C*13 | |
| CHOICE%OBJECT | C*20 | |
| CHOICE%SCAN1 | C*4 | first scan of selected scan range |
| CHOICE%SCAN2 | C*4 | last scan of selected scan range |
| CHOICE%PROCEDURE | C*8 | observing procedure |
| CHOICE%DATE_OBS1 | C*23 | starting date for selection |
| CHOICE%DATE_OBS2 | C*23 | end date for selection |
| CHOICE%TRANSITION | C*20 | spectral line name |
| CHOICE%FRONTEND | C*8 | frontend selection |
| CHOICE%BACKEND | C*8 | backend selection |