The aspect of the investigation into the Monica Lewinsky affair led directly to an impeachable offence was lying under oath. Option A is correct.
Monica Samille Lewinsky is an American activist, television personality, fashion designer, and former White House intern. President Bill Clinton admitted to having had an "inappropriate relationship" with Lewinsky while she worked at the White House in 1995–1996.
As a result of further investigation, there was charges of perjury as well as the impeachment of President Clinton in 1998 by the U.S. House of Representatives.
