#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<queue>
#include<set>
#include<cmath>
#include<string>
#include<map>
#include<vector>
#include<ctime>
#include<stack>
using namespace std;
#define mm(a,b) memset(a,b,sizeof(a))
typedef long long ll;
const long long mod = 1e9 + 7;
const int maxn = 1000;
const ll inf = 1e18;
int n, k, in[maxn], m;

int main()
{
    int t, x, y, flag;
    cin >> t;
    while (t--)
    {
        mm(in, 0);
        scanf("%d%d%d", &n, &m, &k);
        while (m--)
        {
            scanf("%d%d", &x, &y);
            in[x]++, in[y]++;
        }
        flag = 1;
        for (int i = 1; i <= n; ++i)
            if (in[i] < k) { flag = 0; break; }
        if (flag) printf("Yes\n");
        else printf("No\n");
    }
}