B. He was a Marxist who became disillusioned with the repressive policies of the Soviet government.
He was a Revolutionary, so he couldnt be in the Tsar’s army, so its not A.
He wasnt a supporter of Feliks’ Dzierżyńskis Cheka (kind of a police, very brutal), which we know both from his biography aswell as from this text, so its not C.
D. No, he said that the commune state was his (their) dream, and Kerensky was even a noble, which was not good for the commune state.