The correct answer is option 3, Tundra. Tundra is a type of biome characterized by extremely cold temperatures and a lack of trees. The word "treeless" in the question indicates that the vegetation in this biome consists mainly of low-lying plants and grasses. The sparse vegetation is a result of the harsh climate, including freezing temperatures, strong winds, and a short growing season. These conditions make it difficult for trees to survive. Instead, mosses, lichens, and shrubs are common in the tundra. The lack of trees also means that the tundra has low biodiversity compared to other biomes. This unique ecosystem is found in the Arctic and alpine regions and supports a variety of specialized plant and animal species.