Normally magnetos (dualled). Some now use a battery and coil setup, but magnetos are still mostly preferred since they need no other supply of electricity. As long as the magneto rotates it will provide a spark, unlike a coil system which will fail if the battery and electrical system does.
The older ones used magnetos. The newer ones use battery based ignitions.
Magneto. Usually two. It runs on one and has a second in case the first one craps out.
Battery
Magneto
Go read your textbooks and DO YOUR OWN HOMEWORK!
