Why was Zeenat Aman rejected initially by Raj Kapoor for 'Satyam Shivam Sundaram'?

Veteran actor Zeenat Aman who has carved a niche in Bollywood today, was first rejected by Raj Kapoor for ‘Satyam Shivam Sundaram’. But why? RJ Nikki will share this and much more, only on Fundoo Duniya Fultoo facts.