PLZ HURRY Why did Russia sign a treaty and leave the war?

a
They decided to keep the monarchy
b
The country was on the brink of collapse
c
They wanted to explore
d
The country wanted to expand their borders

.elections are held to determine who serves in congress.

so, based on the research i've done. the u.s. government were always on a wild goose chase just to take down castro. he then retired his trone to his brother raul in 2008 due to some health issues. so it's obvious your answer would be:

castro had no allies from which he could receive aid.

hope this and have a fantastic day!

                                                    -wolfiewolffromsketch