Statement 1 is Correct: Crop diversification involves growing a variety of crops in the same area, which enhances soil health, increases biodiversity, and breaks pest cycles, reducing the need for chemical pesticides.

Statement 2 is Correct: Legume intensification refers to the increased cultivation of legumes, which fix atmospheric nitrogen through symbiotic bacteria (Rhizobium), naturally enriching soil fertility and reducing reliance on synthetic fertilizers.

Statement 3 is Correct: A tensiometer measures soil moisture tension, allowing farmers to practice precision irrigation. This conserves water and prevents the leaching of soil nutrients caused by over-watering.

Statement 4 is Incorrect: While vertical farming has certain advantages such as reduced land use and controlled pest management, it is not considered eco-friendly in the Indian context. It relies heavily on artificial lighting and climate control systems, which consume large amounts of electricity — predominantly generated from fossil fuels in India. This high energy footprint undermines its eco-friendly credentials, making it unsuitable to be classified as an eco-friendly agricultural practice in the Indian context.