Which is the longest mountain range on land?

The correct answer is C, Andes. The Andes run down the whole western edge of South America, through seven countries from Venezuela to the southern tip of Chile and Argentina, and form the longest mountain range above sea level. They were raised where the Nazca plate is pushed beneath the South American plate, and they hold Ojos del Salado, the highest volcano in the world.

Option A, the Himalaya, holds the highest peaks in the world, including Everest, K2 in the neighbouring Karakoram and Kangchenjunga, but it is much shorter than the Andes. Option B, the Rockies, run through western North America and are long but not the longest. Option D, the Alps, are the great range of central Europe and are shorter still. Note one further distinction: the mid-ocean ridge system is longer than any of these, but it lies under the sea, which is why the question says on land.