#include<bits/stdc++.h>
using namespace std;

#define pb push_back
#define mp make_pair
#define ALL(x) (x).begin(),(x).end()
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 3e2 + 7;
const int INF = 0x3f3f3f3f;
const ll inf = 0x3f3f3f3f3f3f3f3f;
const int MOD = 1e9 + 7;
const double eps = 1e-7;
const double PI = acos(-1.0);

int n, m, k;

struct Edge{
    int from, to, cap, flow;
    Edge(int u, int v, int c, int f) : from(u), to(v), cap(c), flow(f){}
};

struct Dinic{
    int n, m, s, t;
    vector<Edge> edges;
    vector<int> G[maxn];
    bool vis[maxn];
    int d[maxn];
    int cur[maxn];

    void init(int n){
        this->n = n;
        for (int i = 0; i < n; i++) G[i].clear();
        edges.clear();
    }

    //directed
    void AddEdge(int from, int to, int cap){
        edges.push_back(Edge(from, to, cap, 0));
        edges.push_back(Edge(to, from, 0, 0));
        m = edges.size();
        G[from].push_back(m - 2);
        G[to].push_back(m - 1);
    }

    bool BFS(){
        memset(vis, 0, sizeof(vis));
        queue<int> Q;
        Q.push(s);

        d[s] = 0;
        vis[s] = 1;
        while (!Q.empty()){
            int x = Q.front(); Q.pop();
            for (int i = 0; i < G[x].size(); i++){
                Edge& e = edges[G[x][i]];
                if (!vis[e.to] && e.cap > e.flow){
                    vis[e.to] = 1;
                    d[e.to] = d[x] + 1;
                    Q.push(e.to);
                }
            }
        }
        return vis[t];
    }

    int DFS(int x, int a){
        if (x == t || a == 0) return a;
        int flow = 0, f;
        for (int& i = cur[x]; i < G[x].size(); i++){
            Edge& e = edges[G[x][i]];
            if (d[x] + 1 == d[e.to] && (f = DFS(e.to, min(a, e.cap - e.flow))) > 0){
                e.flow += f;
                edges[G[x][i] ^ 1].flow -= f;
                flow += f;
                a -= f;
                if (a == 0) break;
            }
        }
        return flow;
    }

    int Maxflow(int s, int t){
        for(int i=0;i<edges.size();i++) edges[i].flow=0;
        this->s = s; this->t = t;
        int flow = 0;
        while (BFS()){
            memset(cur, 0, sizeof(cur));
            flow += DFS(s, INF);
        }
        return flow;
    }

    bool judge(){
        s = 0;
        for(t=1;t<n;t++){
            if(Maxflow(s,t) < k) return false;
        }
        return true;
    }
};

Dinic Solver;

int main(){
    //freopen("in.txt", "r", stdin);
    int T;
    cin>>T;
    while(T--){
        cin>>n>>m>>k;
        Solver.init(n);
        for(int i=0;i<m;i++){
            int u, v;
            scanf("%d %d",&u,&v);
            u--; v--;
            Solver.AddEdge(u,v,1);
            Solver.AddEdge(v,u,1);
        }

        if(Solver.judge()) printf("Yes\n");
        else printf("No\n");
    }
    return 0;
}