Correct Answer: (c) Novak Djokovic
Solution:The Australian Open, 2011 men's singles title was won by Novak Djokovic (Serbia) by defeating Andy Murray (Britain). Novak Djokovic also won the men's singles title of Australian Open, 2020 by defeating Dominic Thiem of Austria. Novak Djokovic won the Australian Open 2021 men's singles title by defeating Daniel Medvedev of Russia in the final. In 2022, Rafael Nadal won it by defeating Danill Medvedev.