In the correct arrangement, which of the following represents the sentence that immediately precedes sentence B?

Directions : Below is given a set of six statements, which when arranged in proper order form a coherent paragraph. The sentence E given in bold is placed in correct position, but the parts of the sentence are jumbled. Arrange the sentences in order to form a coherent paragraph and answer the questions that follow.
A. Travelling frequently between the Russian, Ottoman and Qajar Iranian empires, he was one of a class of roving Armenian revolutionaries who collaborated in or took leading roles in the Russian, Iranian and Young Turk revolutions.
B. The Russian revolution of 1905 profoundly undermined the authority of the tsar and helped to generate greater class consciousness, which manifested in the 1917 Bolshevik revolution.
C. Rostom was the nom de guerre of Stepan Zorian (1867-1919) and, like many early 20th-century Armenian revolutionaries, he led a mobile life.
D. Between 1905 and 1911, these upheavals shook the early 20th-century world and transformed the region through an experiment in constitutionalist ideas by attempting to limit the arbitrary rule of autocracies and introducing popular sovereignty. E. autocracy and a firm commitment to social (W) they were, in a word, democratisers who (X) and economic justice and political freedoms (Y) left an important legacy of bold opposition to (Z) F. In all three cases, these Armenian revolutionaries sought the cure to social and political iniquities in constitutionalism, in parliament, and in some degree of popular sovereignty.