The most damaging evidence against president nixon in the watergate impeachment proceedings was the

a) nixon's detailed record of orders to "punish" his enemies.

b) john dean's testimony revealing nixon's personal involvement .

c) discovery of audio tapes of conversations connecting him in attempts to cover up details of the watergate break-in.

d) refusal of the president to take the witness stand in his own defense during the impeachment proceedings in the u. s. senate.
eliminate