The correct answer is: d) All of the above.
Soil testing is important in Arunachal Pradesh to determine soil fertility levels, pH levels, and nutrient deficiencies.
Soil fertility is the ability of a soil to support plant growth. It is determined by the amount of organic matter, nutrients, and water in the soil. Soil fertility can be improved by adding organic matter, such as compost or manure, and by applying fertilizers.
pH is a measure of the acidity or alkalinity of a soil. A pH of 7 is neutral. A pH below 7 is acidic, and a pH above 7 is alkaline. Most plants prefer a soil pH between 6 and 7.5. The pH of a soil can be adjusted by adding lime or sulfur.
Nutrient deficiencies are a lack of essential nutrients in the soil. Nutrient deficiencies can cause plants to grow poorly or not at all. The most common nutrient deficiencies are nitrogen, phosphorus, and potassium. Nutrient deficiencies can be corrected by applying fertilizers.
Soil testing is important in Arunachal Pradesh because it can help farmers to determine the best way to improve their soil and grow healthy crops.