Please show work and explain

Consider the following code:

01: list folderol (int n) 02: { 03: unordered_set t, u; 05: 06: while (t.size() < n) 07: t.insert (rand() % (n*n));

 08: while (u.size() < n) 09: u.insert (rand() % (n*n));

10: 11: list L; 11: for (int i: t) 12: if (u.count(i) > 0) 13: L.push_back(i);

14: return L; 15: }

rand() returns a random non-negative integer and runs in `O(1)` time. Assume that each possible unsigned int value is equally likely to be returned on any given call to rand(). Match the line numbers below to the closest correct complexity expression, giving the single-letter identifier for your chosen complexity. A: O(1) B: O(log n) C: O(sqrt(n)) D: O(n) E: O(n log n) F: O(n sqrt(n)) G: O(n²) H: O(n² log(n)) I: O(n² sqrt(n)) J: O(n³) K: none of these

If the line numbers are preceded by "Avg", give the average case complexity. Otherwise, give the worst case complexity.

Line 7: Avg Line 7: Lines 6-7
Line 13: Line 12: Avg Line 12: Lines 11-13: Avg Lines 11-13:

Line 14: Avg Line 14