#include<bits/stdc++.h>
const int maxn = 5e2 + 10;
std::vector<int> A[maxn], B[maxn];
int mat[maxn], vis[maxn], siz[maxn];
int n, m;
inline int dfs(int u) {
   for (int v : A[u]) {
      if (vis[v]++)
         continue;
      for (int &w : B[v])
         if (! w || dfs(w))
            return w = u, mat[u] = v, 1;
   }
   return 0;
}
inline void Main() {
   scanf("%d%d", &n, &m);
   for (int i = 1, k; i <= m; i++)
      scanf("%d", &k), B[i].clear(), B[i].resize(k);
   for (int i = 1, k; i <= n; i++) {
      scanf("%d", &k), A[i].resize(k);
      for (int &x : A[i]) scanf("%d", &x);
   }
   int ans = 0;
   for (int i = 1; i <= n; i++) {
      memset(vis, 0, sizeof(int) * (m + 1));
      mat[i] = 0, ans += dfs(i);
   }
   printf("%d\n", ans);
   memset(siz, 0, sizeof(int) * (m + 1));
   for (int i = 1; i <= n; i++)
      siz[mat[i]]++;
   memset(vis, 0, sizeof(int) * (n + 1));   
   for (int f = 1; f--; ) {
      for (int i = 1; i <= n; i++)
         if (! vis[i]) {
            int fl = 1;
            for (int j : A[i]) {
               if (j == mat[i]) break;
               fl &= ! siz[j];
            }
            if (fl) {
               printf("%d ", i);
               f = 1, vis[i] = 1, siz[mat[i]]--;
               break;
            }
         }
   }
   puts("");
}
int main() {
   int T; scanf("%d", &T);
   while (T--) Main();
   return 0;
}