Which is very little or nothing

If the government does about the nation’s diet and level of exercise what it has done about most health risks such as smoking and drinking alcohol, which is very little or nothing, then the level of obesity will continue to rise and the health of the nation will continue to fall.

I wonder if "which" means "1" , "2" or "3".

1. smoking and drinking alcohol

2. what it has done about most health risks such as smoking and drinking alcohol

3. If the government does about the nation’s diet and level of exercise what it has done about most health risks such as smoking and drinking alcohol