Answer : 3. "Agronomy"
Explanation :

Haryana Agricultural University Vice Chancellor Professor B.R. Kamboj was awarded the M.S. Swaminathan Award for his significant contribution in the field of agricultural science. Recognized as a scientist/extension specialist, Professor Kamboj's work has been influential in agricultural science. He has published about 300 research papers and articles in various national and international journals, books and technical journals. His award was presented at the International Conference on ‘One Health One World’ in Gwalior, Madhya Pradesh, highlighting his impact on agricultural research and development.