The correct answer is: D. Stan Wawrinka.
Stan Wawrinka won the US Open tennis men’s title in August 2016. He defeated Novak Djokovic in the final in four sets. This was Wawrinka’s third Grand Slam title, after winning the Australian Open in 2014 and the French Open in 2015.
Roger Federer is a Swiss professional tennis player. He is currently ranked No. 9 in the world by the Association of Tennis Professionals (ATP). Federer has won 20 Grand Slam singles titles, the most in history for a male player. He has also won a record 31 Masters 1000 titles and a record six ATP Finals titles.
Rafael Nadal is a Spanish professional tennis player. He is currently ranked No. 3 in the world by the Association of Tennis Professionals (ATP). Nadal has won 21 Grand Slam singles titles, the most in history for a male player. He has also won a record 36 Masters 1000 titles and a record 14 French Open titles.
Mahesh Bhupathi is an Indian former professional tennis player. He is currently the co-founder and CEO of IPTL. Bhupathi was ranked No. 1 in the world in doubles in 1999 and 2001. He has won 11 Grand Slam doubles titles, the most in history for an Indian player. He has also won a record 43 ATP Masters 1000 doubles titles.