To answer this question, we need to understand the background of the movie "Dangal."
"Dangal" is a Bollywood movie that was released in 2016. It is based on the true story of the Phogat family, specifically Mahavir Singh Phogat, who is a former Indian wrestler and senior Olympic coach.
Mahavir Singh Phogat trained his daughters, Geeta Phogat and Babita Kumari, in the sport of wrestling and helped them achieve remarkable success in the field. The movie showcases their journey and the challenges they faced in pursuit of their wrestling careers.
Therefore, the correct answer is option D - Mahavir Singh Phogat.