For about two weeks my civic has been getting increasingly difficult to start. I have to push the clutch all the way to the floor, bury the foot in order to get the starter to engage. Finally won't kick over. Battery is good. How do I know if it is a relay or the starter? Which relay? The car has 280,500 miles, finally got the new knocked off it. Normally runs like bat out of hell. Could it have anything to do with clutch adjustment?

The clutch is wearing and you need to check the clutch pedal height adjustment. Pedal height is increased by loosening the locknut to the clutch pedal adjusting mechanism, rotating the threaded pushrod to increase pedal height, and retightening locknut.