"Who Wants to Be a Millionaire": Which country has the longest coastline?

In the September 3 episode of the Polish "Who Wants to Be a Millionaire" on Polsat, a contestant was stumped by the 25,000-złoty question: which country has the world's longest coastline? He asked host Hubert Urbański for help. The answer is Canada, with a coastline exceeding 202,000 km.