how to index zeros or remove zeros for indexing?

if

if true
  % code
A=[1 2 3 0 0 4]
B=[1 3 5 2 4 5]
C=[1  56 65 65 65; 4 5 45 546 4; 54 54 51 21 21;  4 453 3645 534 4;  54 554  54 541 1]
D= C(A,B)
end

i want D to be zero when A is zero but it shows indexing is not valid

Answer 1

[Bruno Luong]

D=zeros(length(A),length(B))
D(A>0,B>0)=C(A(A>0),B(B>0))