#include <bits/stdc++.h>
using namespace std;
void bajar() {
  int n;
  scanf("%d", &n);
  vector<int> a(n);
  for (int &i : a) scanf("%d", &i);
  vector<int> b(n + 1);
  b[0] = 0;
  for (int i = 1; i <= n; i++) b[i] = b[i - 1] + a[i - 1];
  for (int i = 1; i <= n; i++) {
    for (int j = i; j <= n; j++) {
      int yi = b[j] - b[i - 1];
      if (yi > 0 && yi % 2 == 0) {
        printf("%d\n", j - i + 1);
        for (int k = i - 1; k < j; k++) printf("%d ", k + 1);
        printf("\n");
        return;
      }
    }
  }
  printf("-1\n");
}
int main() {
  int T = 1;
  scanf("%d", &T);
  while (T--) bajar();
  return 0;
}
