I'm impressed how many people got this one right! Yes, it was C.  Bill Clinton was 23 years younger than Bob Dole in 1996.  I really wanted it to be D though, because Winfield Scott, the longest-serving general in US history (50 years!) was known as Old Fuss and Feathers.  But he was only 18 years older than Franklin Pierce.  Reagan was 17 years older than Mondale.  The second biggest age spread before now was actually Clinton and the first President Bush, who was 22 years older than Bill in 1992.