For today's Geo Quiz we're zeroing in on the world's favorite tuber.
We're talking about the potato. It's the world's 4th largest food crop -- behind rice, wheat, and corn. China produces the most potatoes these days.
But we're looking for the country where the potato originated. The plant was first domesticated in the shadow of the Andes Mountains some 8,000 years ago.
Today nearly 3,000 varieties of potato are grown throughout this mountainous country. Villages in the country's southern Ayacucho region take pride in their crop. They celebrate the season's first potato harvest with offerings and music.
So name the country that's the ancestral home of the potato.
We were looking for a country on South America's Pacific coast. Among its notable accomplishments -- it's the ancestral home of the potato.
The answer is Peru.
And it turns out that the potato is not only a part of Peru's history. It may also play a vital rule in its future. Yes, the humble spud could provide an answer to Peru's long-standing problems of hunger and poverty.
The BBC's Dan Collyns reports from Ayacucho, Peru.