What was Nixon's role in the Watergate scandal?

A. Nixon lied under oath when questioned about the break-in.

B. Nixon ordered the break-in.

C. Nixon attempted to obstruct the investigation of the break-in.

D. Nixon broke into the Democratic headquarters at the Watergate building.

It is letter a. Nixon lied under oath when questioned about the break-in. He claimed to have no knowledge of the break-ins but it was revealed that he recorded meetings that he had in his office. This led to the conviction of many of his top aides. Rather than face impeachment, he resigned. It can also be letter c. because he did not give up all of his tapes and that is an obstruction of the investigations.