CREATE TABLE table_25055040_22 (youth_classification VARCHAR(255), sprint_classification VARCHAR(255), most_courageous VARCHAR(255))
When Mark Cavendish wins sprint classification and Maarten Tjallingii wins most courageous, who wins youth classification?
    
SQL: SELECT youth_classification FROM table_25055040_22 WHERE sprint_classification = "Mark Cavendish" AND most_courageous = "Maarten Tjallingii"