Who among the following became the Chief Minister of Uttarakhand in March, 2021?

The correct answer is Tirath Singh Rawat.

Explanation:
In March 2021, political developments in Uttarakhand led to a change in the state's leadership. Trivendra Singh Rawat, who had been serving as the Chief Minister since March 2017, resigned from his post on March 9, 2021.
Following his resignation, the Bharatiya Janata Party (BJP) legislative party chose Tirath Singh Rawat as the new leader. He was sworn in as the 9th Chief Minister of Uttarakhand on March 10, 2021.

Key Facts about Tirath Singh Rawat's Tenure:
- He served as the Chief Minister of Uttarakhand from March 10, 2021, to July 4, 2021.
- His term was relatively short (nearly four months) because he was a Member of Parliament (Lok Sabha) at the time and needed to be elected to the Uttarakhand Legislative Assembly within six months to continue as Chief Minister. Due to the COVID-19 pandemic and constitutional constraints, holding a by-election became difficult, leading to his resignation.
- He was succeeded by Pushkar Singh Dhami in July 2021.