Consider the following definition of the function removeFirst:

1. var removeFirst = function (n,ns) {
2.    if (fp.isNull(ns)) {
3.        return [ ];
4.    } else if (fp.isEq(n,fp.hd(ns))) {
5.        return fp.tl(ns);
6.    } else {
7.        return fp.cons(fp.hd(ns),removeFirst(n,fp.tl(ns)));
8.    }
9. }

If you want to modify this function to make it remove all occurrences of n in ns instead of just the first one, you could accomplish this by making a small change in one line and leaving the rest of the function unchanged. Which line is it?

5
  1. 2
  2. 3
  3. 4
  4. 5
  5. 7

Remember that, on an exam or if called upon in class, you will have to both identify the line number and spell out the specific code change.