B. He sincerely believe that Johnson had not committed an impeachable offense.
Senator Ross's vote allowed Johnson to stay in office, as they failed to reach the 2/3's majority in order to impeach. Ross believed that even if Johnson had been outside of his authority in replacing Stanton, it was not an offense worthy of impeachment.
James Buchanan
John C. Fremont
Millard Fillmore
France Is the right answer I did the same test