Concept:The tallest person is the one who is taller than all others in the combined comparison.Explanation:First statement gives: Raju>Aman>Raj.Second statement gives: Roshan>Raju>Imran.Combining both: Roshan>Raju>Aman>Raj.Also, Raju>Imran.So Roshan is taller than everyone.Answer:Roshan is the tallest.