自問自答
No cyclist has ever won all four Tour de France jerseys (yellow, green, polka dot, and white) in the same year. While Eddy Merckx won the yellow (overall), green (points), and polka dot (mountains) jerseys in 1969, the white jersey (best young rider) didn't exist at the time. In theory, a rider could win all four, but it would require dominating the general classification, points classification, mountains classification, and also being the best young rider under 26 years old at the start of the Tour. This has never happen