Option 1 -> Prasanta Chandra Mahalanobis was a renowned statistician who developed the Mahalanobis distance and contributed to economic planning in India.
Option 2 -> Subrahmanyan Chandrasekhar was an astrophysicist and Nobel laureate known for his work on stellar structure and the Chandrasekhar limit.
Option 3 -> Raj Reddy is a computer scientist recognized for his contributions to artificial intelligence and robotics.
Option 4 -> Birbal Sahni was a paleobotanist who extensively studied plant fossils of the Indian subcontinent and founded the Birbal Sahni Institute of Palaeobotany in Lucknow.
Hence, Option 4: Birbal Sahni -> He is celebrated as the founder of paleobotany in India and made groundbreaking contributions to understanding the fossilized flora of the Indian subcontinent, particularly during the Gondwana period -> correct