Which of the Following Statements Characterizes the Congressional Impeachment of Andrew

Which of the following statements characterizes the congressional impeachment of Andrew Johnson?

A) Johnson was the only president ever to be impeached and removed from office in American history.
B) Radical Republicans failed to remove Johnson from office,but they damaged his power and authority.
C) Moderate Republicans joined with the Radicals to impeach Johnson,but the Supreme Court overturned his impeachment on appeal.
D) In return for Johnson's promise not to oppose the Radical Republicans' plans,the Senate acquitted him.