### Instruction: what is the greenest country ion the world
### Input: Coming in at first place is Sweden. Sweden ranks highly across the studies, coming in 5th place on the EPI, 9th for the GFI, and 4th for the lowest annual average PM2.5 concentration at 6.6 μg/m³.

However, like most European countries Sweden’s main downfall is its CO2 emissions per capita, ranking only 28th place with 4.18 tonnes (4th in Europe).

Some of Sweden’s highlights are that it has a perfect score in the EPI for protecting marine ecosystems and it ranks second in the GFI’s CO2 emissions growth in transport sector indicator.
### Response: sweden