The climate characterized by fertile soil is typically associated with the Rainforest. Rainforests, particularly tropical rainforests, support rich biodiversity and contribute to nutrient-rich soils due to the decomposition of organic material.
Deserts tend to have poor soil fertility due to a lack of moisture, and tundra regions have limited vegetation and nutrient availability as well.
Thus, among the options provided, the best answer would be Rainforest.