The correct option is Tundra vegetation.
Explanation
Natural vegetation is primarily determined by climatic conditions, specifically temperature and moisture. Tundra vegetation is a biome characterized by extremely low temperatures, short growing seasons, and the presence of permafrost, which restricts the growth of deep-rooted plants like trees.
Option Analysis
- Tundra vegetation is correct: Tundra vegetation is found in the high latitudes (Arctic region) and high altitudes (Alpine region). Due to the extreme cold and frozen subsoil, large trees cannot survive. The vegetation consists mainly of low-growing plants such as mosses, lichens, and small shrubs, which can survive the harsh conditions and short summers.
- Tropical Evergreen is incorrect: Tropical Evergreen forests are found in regions with heavy rainfall and high temperatures throughout the year. They are characterized by dense, multi-layered vegetation comprising tall hardwood trees like ebony, mahogany, and rosewood, rather than simple non-vascular plants like mosses and lichens.
- Moist Deciduous is incorrect: Moist Deciduous forests are typical of monsoon climates with moderate rainfall. They contain commercially important timber trees like teak and sal, which shed their leaves during the dry season.
- Thorn Forests is incorrect: Thorn Forests are found in semi-arid and arid regions with low rainfall. The vegetation here consists of thorny trees and bushes (e.g., Acacia, Cactus) adapted to conserve water, distinct from the cold-adapted flora of the Tundra.
Key Takeaway
Mosses and lichens are the dominant vegetation in Tundra regions, where extreme cold and permafrost prevent the growth of larger, vascular plants.