What is one way that historians can establish the authenticity of a primary source?

Which best describes alexis de tocqueville

Which of the following statements occurred last in the official overthrow of the russian provisional government in october of 1917? the bolsheviks campaigned for support of their political platform. the bolsheviks organized an assault and stormed the winter palace. the bolsheviks and trotsky’s militia seized key targets in petrograd. vladimir lenin established himself as the leader of the bolsheviks. i know the answers a and d are inccorect.

Which of these works from the italian renaissance exhibits contrapposto?