Question

the tsar lost control of his soldiers during the february revolution and could not enforce his rule, so he was forced to
o flee russia.
o step down.
o establish a new government.
o lead a militia to fight to regain power.

Explanation:

During the February Revolution, the tsar lost control of his soldiers and couldn't enforce his rule. In such a situation, the typical outcome for a leader who has lost the means to govern (like control of the military) is to step down. There is no historical evidence that he fled Russia immediately after losing control during the February Revolution in this context. He couldn't establish a new government as the revolution was against his rule. And he didn't lead a militia to regain power effectively as he had lost control of the main military forces.

Answer:

step down.