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

in the 1800s, locomotives powered by steam made transportation faster and cheaper. the resulting rapid growth of railroads led to the connection of the atlantic and pacific railroad in oklahoma city in 1897.

in the last years of the century, the improvement of steam-based engines the expansion and growth of railroads. this growth increased when the companies started to build and expand, such as the atlantic and pacific railroad, which connected new mexico with california, and missouri with oklahoma. many of these new networks were built in oklahoma, and these changes transportation henceforward.

according to my calculation, the answer is d.