Maybe I didn't understand well your first post and I answered wrongly but you could have seen in the description for C this line:

`I = {12, 15}; // result = "(2 12)(3 27)(5 15)"

and in initial solution:

char* sumOfDivided(int* lst, int l) {
  // your code
}

which shows that the return is a char *.
In the description I will replace the line:

The final result has to be given as a string in Java, C#, C++ and as an array of arrays in other languages.

by
"The final result has to be given as a string in Java, C#, C, C++ and as an array of arrays in other languages".

since in that line I forgot "C". I am sorry and thanks for your post.

I am afraid you didn't understand well the tests. You have to return a Data * but to ease the testing your return is transformed by the tests in a string. This transformation has not to be done by yourself, it is made by the kata. Note at the top of the age that 47 guys passed the C kata.