International Mountain Day was observed by United Nations on December 11. Consider the following statements with respect to mountains and choose the incorrect option.

• A. Mountains cover around 22 percent of the earth’s land surface.
• B. Mountain tourism attracts nearly 15-20 per cent of global tourism.
• C. Mountains are home to 13 percent of world’s population.
• D. Mountain house 81 percent of all Biosphere reserve.