Question: Who is the oldest senator currently serving in congress?
Disambiguated questions and answers: question: Who is the oldest Senator serving in Congress from January 3, 2015 t0 December 8, 2016?
Who is the oldest Senator serving in Congress from July 30, 2013 to January 3, 2015?
Who is the oldest Senator serving in Congress from October 20, 2009 t0 July 30, 2013?
answer: John Glenn
Edward Brooke
Harry F. Byrd Jr.
Natural Questions answer: Dianne Feinstein (from the Wikipedia article "List of longest-living United States Senators")