#include<cstdio>

 #include<cstring>

 #include<queue>

 #include<algorithm>

 using namespace std;

 #define INF (1<<30)

 #define MAXN 555

 #define MAXM 555*555*2

 struct Edge{

     int v,cap,flow,next;

 }edge[MAXM];

 int vs,vt,NE,NV;

 int head[MAXN];

 void addEdge(int u,int v,int cap){

     edge[NE].v=v; edge[NE].cap=cap; edge[NE].flow=;

     edge[NE].next=head[u]; head[u]=NE++;

     edge[NE].v=u; edge[NE].cap=; edge[NE].flow=;

     edge[NE].next=head[v]; head[v]=NE++;

 }

 int level[MAXN];

 int gap[MAXN];

 void bfs(){

     memset(level,-,sizeof(level));

     memset(gap,,sizeof(gap));

     level[vt]=;

     gap[level[vt]]++;

     queue<int> que;

     que.push(vt);

     while(!que.empty()){

         int u=que.front(); que.pop();

         for(int i=head[u]; i!=-; i=edge[i].next){

             int v=edge[i].v;

             if(level[v]!=-) continue;

             level[v]=level[u]+;

             gap[level[v]]++;

             que.push(v);

         }

     }

 }

 int pre[MAXN];

 int cur[MAXN];

 int ISAP(){

     bfs();

     memset(pre,-,sizeof(pre));

     memcpy(cur,head,sizeof(head));

     int u=pre[vs]=vs,flow=,aug=INF;

     gap[]=NV;

     while(level[vs]<NV){

         bool flag=false;

         for(int &i=cur[u]; i!=-; i=edge[i].next){

             int v=edge[i].v;

             if(edge[i].cap!=edge[i].flow && level[u]==level[v]+){

                 flag=true;

                 pre[v]=u;

                 u=v;

                 //aug=(aug==-1?edge[i].cap:min(aug,edge[i].cap));

                 aug=min(aug,edge[i].cap-edge[i].flow);

                 if(v==vt){

                     flow+=aug;

                     for(u=pre[v]; v!=vs; v=u,u=pre[u]){

                         edge[cur[u]].flow+=aug;

                         edge[cur[u]^].flow-=aug;

                     }

                     //aug=-1;

                     aug=INF;

                 }

                 break;

             }

         }

         if(flag) continue;

         int minlevel=NV;

         for(int i=head[u]; i!=-; i=edge[i].next){

             int v=edge[i].v;

             if(edge[i].cap!=edge[i].flow && level[v]<minlevel){

                 minlevel=level[v];

                 cur[u]=i;

             }

         }

         if(--gap[level[u]]==) break;

         level[u]=minlevel+;

         gap[level[u]]++;

         u=pre[u];

     }

     return flow;

 }

 int n,m,k,h[];

 bool G[][];

 bool isok(int mx){

     vs=; vt=; NV=n; NE=;

     memset(head,-,sizeof(head));

     for(int i=; i<k; ++i) addEdge(h[i],vt,);

     for(int i=; i<=n; ++i){

         for(int j=; j<=n; ++j){

             if(G[i][j]) addEdge(i,j,mx);

         }

     }

     return ISAP()==k;

 }

 int main(){

     int t,a,b;

     scanf("%d",&t);

     while(t--){

         memset(G,,sizeof(G));

         scanf("%d%d%d",&n,&m,&k);

         for(int i=; i<k; ++i) scanf("%d",h+i);

         for(int i=; i<m; ++i){

             scanf("%d%d",&a,&b);

             G[a][b]=G[b][a]=;

         }

         int l=,r=k;

         while(l<r){

             int mid=l+r>>;

             if(isok(mid)) r=mid;

             else l=mid+;

         }

         printf("%d\n",l);

     }

     return ;

 }