Consider the following function definition:

1.  var qs = function (ns) {
2.      if (fp.isNull(ns)) {
3.          return [ ];
4.      } else {
5.          return join(
6.                      fp.hd(split(fp.hd(ns),fp.tl(ns))),
7.                      fp.cons(fp.hd(ns),
8.                              fp.hd(fp.tl(split(fp.hd(ns),fp.tl(ns)))))
9.                     );
10.     }
11. };

The qs function above takes as input a (flat) list of integers and uses the split and join functions to compute its output.
Now, you want this function to sort any list of integers in ascending order. Instead it behaves in the following way:

 
> qs([5,1,9,2,7,3]) 
[ 3, 2, 1, 5, 7, 9 ] 

Which one of the following options best characterizes the line(s) that will have to change to solve this problem?

• Only line 6 has to change.
• Only line 7 has to change.
• Only line 8 has to change.
• Lines 6, 7, and 8 all have to change.