Who is Lata Mehra from A Suitable Boy: A Novel and what is their importance?

Lata is arguably the central character of the novel. She is the younger daughter of Mrs. Rupa Mehra, a widow. She is first seen at the wedding of her sister Savita to Pran Kapoor. Lata is a student at the university. She has a quick mind and is quite well read, though somewhat naive about life and relationships. Lata questions the idea of an arranged marriage like that of her sister where the couple know nothing at all about each other.