This car uses break fluid between master and slave cylinder. master being on under the clutch padel, and slave is on top of gearbox/under the car battery box. So both of these cylinders are potential to be an issue.
But tell us - did it happen all of sudden like this: yesterday no problem at all meaning soft clutch padel, and returning normal - today problem hard clutch padel and returning slowly?
If the clutch pedal has been crazy hard before there is good chance you actually have to replace the clutch + clutch bearing. if the clutch still makes it possible to shift gears when clutch pedal down, and if it makes not possible to shift gears when clutch pedal is up I would proceed with replacing clutch and leave both of the cylinders.