1
2 2
1 1
1 2
 1
1 3
3
1 2 3
 1
1 1
1000
1000
 1
2 2
2 2
2 2
 5
4 5
10 8 6 4
1 2 3 4 5
1 1
3
3
1 1
3
2
5 3
1000 2 2 2 3
3 1 5
5 5
1 2 3 4 5
1 2 3 4 5
 1
4 4
1 1 1 1
1 2 3 4
 1
2 3
1 1
1 2 3

YES
1 1
 YES
1 3
 YES
1 1000
 YES
1 2
 YES
1 4
YES
1 3
NO
YES
1 3
YES
1 1
 YES
1 1
 YES
1 1

#include <bits/stdc++.h>
using namespace std;
int testCase;
int iinf = 1e9 + 1;
long long inf = 1e16 + 1;
void solve() {
  int m, n, elem;
  cin >> m >> n;
  set<int> a, b, c;
  for (int i = 0; i < m; i++) {
    cin >> elem;
    a.insert(elem);
  }
  for (int i = 0; i < n; i++) {
    cin >> elem;
    b.insert(elem);
  }
  set_intersection(a.begin(), a.end(), b.begin(), b.end(),
                   inserter(c, c.begin()));
  if (c.size() == 0)
    cout << "-1\n";
  else {
    cout << "YES\n" << *c.begin() << "\n";
  }
}
int main() {
  cin >> testCase;
  while (testCase--) {
    solve();
  };
}
