#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;

#define Int register int
#define MAXN 305

int n,m,k;
int du[MAXN];

void read (int &x)
{
    x = 0;char c = getchar();int f = 1;
    while (c < '0' || c > '9'){if (c == '-') f = -f;c = getchar();}
    while (c >= '0' && c <= '9'){x = (x << 3) + (x << 1) + c - '0';c = getchar();}\
    x *= f;return ;
}

void write (int x)
{
    if (x < 0){x = -x;putchar ('-');}
    if (x > 9) write (x / 10);
    putchar (x % 10 + '0');
}

signed main()
{
    int times;
    read (times);
    while (times --)
    {
        read (n),read (m),read (k);
        memset (du,0,sizeof (du));
        for (Int i = 1;i <= m;++ i)
        {
            int u,v;
            read (u),read (v);
            du[u] ++,du[v] ++;
        }
        int g = 0;
        for (Int i = 1;i <= n;++ i)
        {
            if (du[i] < k)
            {
                g = 1;
                break;
            }
        }
        if (g) puts ("No");
        else puts ("Yes");
    }
}