Related Clues:

• Model conundrum
• Awful person with no end of affectation?
• A hard question for one, a sitter for another
• Religious leader died, resurrected around the end of April; it's an enigma
• It may be used to sort out a difficult problem
• Tricky question presenting no difficulty in test paper, ultimately
• Pervade conundrum
• Its entertainment value is questionable
• Puzzling question - sieve
• Problem - model
• Model - problem
• Ingenious puzzle - sieve
• Brainteaser - sieve
• Question - a sitter
• Sphinx's conundrum?