The rupee symbol we now use came from D. Udaya Kumar, a postgraduate from IIT Guwahati whose entry beat thousands of others in an open competition held by the Government of India. The Union Cabinet gave it formal approval on 15 July 2010. His design merges the Devanagari ra with a Latin R stripped of its vertical stem, topped by two parallel horizontal lines meant to recall the tricolour and hint at an equality sign, reflecting the idea of a currency that stands strong and equal on the world stage. With this symbol, India joined a small group of countries, alongside the US dollar, the pound, the euro and the yen, that have their own distinct currency mark.
None of the other three had a role in this. Dilip Chhabria is known for automobile design work in India, and Tarun Tahiliani is a leading fashion designer, both fields unrelated to currency symbols. S. Arun Kumar is simply a name close enough to the correct one to serve as a distractor, but he did not create the rupee symbol. The correct answer remains D. Udaya Kumar.