A farmer in a semi-arid area claims that his farming practice is very environment friendly. Which of the following practices on his farm can justify his claim ? 1. Planting a tree belt. 2. Practising crop rotation. 3. Carrying out a large scale irrigation system. 4. Using organic fertilizers. Select the correct answer using the code given below :3 and 4 only 1,2 and 41, 3 and 41 and 2 only