#include <bits/stdc++.h>
int main() {
  int m, i, n, l, s, flag;
  int a[100];
  scanf("%d", &m);
  while (m--) {
    flag = 0, l = 0;
    scanf("%d", &n);
    for (i = 1; i <= n; i++) scanf("%d", &a[i]);
    for (i = 1; i <= n; i++) {
      if (a[i] % 2 == 0) {
        printf("1\n");
        printf("%d\n", i);
        flag = 1;
        break;
      } else {
        if (l == 0) {
          l = i;
        } else {
          s = i;
          flag = 1;
          printf("2\n");
          printf("%d %d\n", l, s);
          break;
        }
      }
    }
    if (flag == 0) printf("-1\n");
  }
  return 0;
}
