Answer:
A. Vladimir Lenin returned to lead the Russian Revolution
Explanation:
A. Vladimir Lenin returns shortly after Czar Nicholas abdicates in February
B. Leon Trotsky escaping to Mexico doesn't happen for a while until Lenin dies. Trotsky escapes since he knows Stalin will kill him for being a political opponent
C. The New Economic Policy happens in 1921, way after 1918
D. The Red Army wins the civil war in 1919
He was the principle chief
Laidsez-claire means capitalism government.
In this context alliance would mean to come to a formal agreement to help each other.