The correct answer is option 'D', Coochbehar.
Let's discuss why Coochbehar is the district in West Bengal with the highest production of tobacco.

1. Introduction to Coochbehar:
Coochbehar is a district located in the northern part of West Bengal, India. It is the largest district in terms of area and is known for its agricultural productivity. The district has favorable climatic conditions and fertile soil, making it suitable for the cultivation of various crops, including tobacco.

2. Favorable Climatic Conditions:
Coochbehar experiences a sub-tropical climate with moderate rainfall. The region has a long growing season, which is favorable for the cultivation of tobacco. The temperature and humidity levels support the growth of tobacco plants, leading to higher yields.

3. Fertile Soil:
The district of Coochbehar has fertile soil, rich in organic matter and essential nutrients required for the growth of tobacco plants. The soil is well-drained and loamy, creating a favorable environment for the cultivation of tobacco. The presence of nutrients in the soil enhances the quality and quantity of tobacco produced.

4. Agricultural Practices:
Farmers in Coochbehar have adopted effective agricultural practices for tobacco cultivation. They use modern techniques, including the use of quality seeds, proper irrigation methods, and appropriate fertilizers. These practices ensure higher yields and better quality tobacco production.

5. Economic Importance:
Tobacco cultivation plays a significant role in the economy of Coochbehar. It provides employment opportunities to a large number of farmers and laborers in the region. The revenue generated from tobacco production helps in the overall development of the district.

6. Demand and Market:
The demand for tobacco is high in both domestic and international markets. Coochbehar's tobacco production meets the demand of various industries, including the tobacco processing industry, cigarette manufacturing units, and export markets. The favorable market conditions and demand for tobacco contribute to its high production in the district.

7. Government Initiatives:
The government of West Bengal has taken several initiatives to promote and support tobacco cultivation in Coochbehar. They provide subsidies, loans, and technical assistance to farmers, encouraging them to engage in tobacco farming. These initiatives have further boosted the production of tobacco in the district.

In conclusion, Coochbehar district in West Bengal has the highest production of tobacco due to its favorable climatic conditions, fertile soil, effective agricultural practices, economic importance, demand and market conditions, and government support. These factors collectively contribute to making Coochbehar a prominent tobacco-producing region in West Bengal.