#include <bits/stdc++.h>
using namespace std;
int i, j, k, n, m, t, sum, vis[150], x, y, it;
long long f[105], res, f2[105][105];
vector<int> v[205];
void dfs(int x, int fa, int d) {
  vis[x] = 1;
  if (d == j) {
    f[x]++;
    return;
  }
  for (auto i : v[x]) {
    if (i == fa) {
      continue;
    }
    dfs(i, x, d + 1);
    f[x] += f[i];
  }
}
int main() {
  scanf("%d", &t);
  while (t--) {
    scanf("%d%d", &n, &m);
    for (i = 1; i <= n; i++) {
      v[i].clear();
    }
    for (i = 1; i < n; i++) {
      scanf("%d%d", &x, &y);
      v[x].push_back(y);
      v[y].push_back(x);
    }
    if (m == 2) {
      printf("%d\n", n * (n - 1) / 2);
      continue;
    }
    res = 0;
    for (i = 1; i <= n; i++) {
      for (j = 1; j <= n; j++) {
        memset(vis, 0, sizeof(vis));
        memset(f, 0, sizeof(f));
        memset(f2, 0, sizeof(f2));
        dfs(i, 0, 0);
        f2[0][0] = 1;
        it = 0;
        for (auto jj : v[i]) {
          if (f[jj] == 0) {
            continue;
          }
          for (k = 0; k <= it; k++) {
            f2[it][k] %= 1000000007;
            f2[it + 1][k] += f2[it][k];
            f2[it + 1][k + 1] += f2[it][k] * f[jj] % 1000000007;
          }
          it++;
        }
        res += f2[it][m];
        res %= 1000000007;
      }
    }
    printf("%lld\n", res);
  }
}
