Which is most likely the author’s primary reason for selecting 1863 as the setting in this passage?

A to explain family relationships in nineteenth-century America
B to show how the roles of men and women have changed since 1863
C to entertain readers while teaching them about the hardships of farming and war in the past
D to explore why soldiers volunteered to fight in the Civil War and how it affected their families

Question

Which is    most likely the author’s primary reason for selecting 1863 as the setting in this passage?  
 
    A     to explain family relationships in nineteenth-century America  
    B     to show how the roles of men and women have changed since 1863  
    C     to entertain readers while teaching them about the hardships of farming and war in the past  
    D     to explore why soldiers volunteered to fight in the Civil War and how it affected their families