Explanation:

- Option 1: Sawarn Singh

Sawarn Singh is an Indian rower, but he is not the first to win gold at the Asian Games in 2010.

- Option 2: Dattu Baban Bhokanal

Dattu Baban Bhokanal is a renowned Indian rower, known for his later achievements, but not for a gold at the 2010 Asian Games.

- Option 3: Bajrang Lal Takhar

Bajrang Lal Takhar is the correct answer. He made history by becoming the first Indian rower to win a gold medal at the Asian Games in 2010. He won in the men's single sculls event.

- Option 4: Dushyant Chauhan

Dushyant Chauhan is another notable Indian rower but did not achieve the gold in 2010.