Mr and Mrs Tan have five children - 4 boys and a girl. Their names are Alfred, Brenda, Charles, Darius and Eric.
For some reason, they refuse to tell each other their respective favourite colours.
However, they know each of them likes exactly one of the colours apricot, blue, cherry, dun and emerald such that none of them likes a colour that begins with the same letter as their name.
One day, the following weird discussion took place.
Brenda whispered into Alfred's ear, "I dislike apricot."
Alfred then whispered into Charles' ear, "And I really dislike cherry."
Eric, the youngest child, felt that this was pointless. He finally announced, "My favourite colour is dun."
Now Charles said to Alfred, "All these aren't helpful! I still cannot determine your favourite colour!"
Just then Alfred said to Brenda, "But sis, I do know your favourite colour now!"
Let's assume all five siblings are perfectly truthful and rational. What do you think Darius' favourite colour is?