I came across one question in which the Karnaugh map for some function is given and using it, i have to find a simple function which gets mapped onto that map.

Finding a simple function for a given Karnaugh diagram-img03402-20140518-0956.jpg

My Attempt:

Corresponding to every shaded square there will be a boolean expression of the form, $0000,0010,1010,..$ etc.

What I did was that I added the minterms corresponding to those expressions which had value $1$ i.e. I added the minterms corresponding to $0000,0010,1010,1000,1011,1111,1101,1110$.

My questions:

First, i am not sure about, what, is actually meant by "$simple function$" here, does it simply mean that i have to add the minterms which have value $1$ and find a simplified expression or do i have to make pairs of ones in the karnaugh diagram and find the minimal form for the function ?

Second,will there be a unique simple function ? or would it depend on the way in which sequence $0's$ and$1's$ are chosen?