confronting cell with abelians (logic values)

I have a question about the way to extract some data from a cell based on some "indices" (in this case I want only to get as an output the "1-associated" values, e.g.:

A={'a' 'b' 'c'; 'd' 'e' 'f';'g' 'h' 'i'}

B=eye(3);

...formula to compare the arrays....
    
C={'a' '0' '0'; '0' 'e' '0';'0' '0' 'i'}

or 

C={'a' nan nan; nan 'e' nan;nan nan 'i'}

I really cannot see the way to easily do it. Thanks

Answer 1

[the cyclist]

Here is one way:

C = A;
C(~B) = {'0'};

Answer 2

[Ameer Hamza]

[A{~B}] = deal('0');

[the cyclist]

A simpler version of this idea is

A(~B) = {'0'}

Caution: this solution overwrites A itself, which you may not want.