Some parts of a sentence have been jumbled up, and labelled P, Q, R and S. Select the option that gives the correct sequence in which these parts can be rearranged to form a meaningful and grammatically correct sentence.

The Government reforms imposed by

P. series of major social, political, legal and

Q. the Great Reforms by historians, were a

R. governmental reforms in the

S. Tsar Alexander II of Russia, often called

Russian Empire carried out in the 1860s.