The establishment of coffee and tea plantations in Kerala by the British led to significant:

The correct answer is: D) All of the above

The establishment of coffee and tea plantations in Kerala by the British led to significant ecological changes, economic development, and social transformation.

• Ecological changes: The establishment of coffee and tea plantations led to the clearing of large areas of forests, which had a significant impact on the local environment. The loss of forests led to soil erosion, changes in the water cycle, and the loss of biodiversity.
• Economic development: The coffee and tea plantations were a major source of income for the British and for the local people who worked on them. The plantations also led to the development of infrastructure, such as roads and railways, which helped to stimulate the local economy.
• Social transformation: The establishment of coffee and tea plantations led to the displacement of local people from their land and the disruption of traditional ways of life. The plantations also led to the introduction of new social and economic relations, such as the development of a plantation class and the emergence of a new class of workers.

In conclusion, the establishment of coffee and tea plantations in Kerala by the British led to significant ecological changes, economic development, and social transformation.