#include<iostream>

 #include<cstdio>

 #include<queue>

 #include<cstring>

 #include<vector>

 #include<algorithm>

 #define INF 0x3f3f3f3f

 #define M(a,b) memset(a,b,sizeof(a))

 typedef long long LL;

 using namespace std;

 const LL mod = ;

 int N,M;

 int dp[][];

 int tot[];

 struct node

  {

      int t,nxt;

  }edge[*];

 int headline[];

 int E;

 void add(int f,int t)

  {

      E++;

      edge[E].t = t;

      edge[E].nxt = headline[f];

      headline[f] = E;

  }

 void dfs(int u, int fa)

 {

     for(int i = headline[u];i != -;i = edge[i].nxt)

     {

         int t = edge[i].t;;

         if(t!=fa)

         {

             dfs(t,u);

             for(int j = ;j<=M;j++)

             {

                 if(tot[t]-dp[t][j]<)

                 dp[u][j] = ((LL)dp[u][j]*(tot[t]-dp[t][j]+mod)%mod)%mod;

                 else

                 dp[u][j] = ((LL)dp[u][j]*(tot[t]-dp[t][j])%mod)%mod;

             }

         }

     }

     for(int i = ;i<=M;i++)

     {

         tot[u] = (tot[u]+dp[u][i])%mod;

     }

     return;

 }

 int main()

 {

     while(scanf("%d%d",&N,&M)==)

     {

         int t;

         M(dp,);

         M(headline,-);

         M(tot,);

         E=;

         for(int i = ;i<=N;i++)

         {

             scanf("%d",&t);

             int a;

             for(int j = ;j<t;j++) {scanf("%d",&a);dp[i][a]=;}

         }

         int u,v;

         for(int i = ;i<N-;i++)

            {

              scanf("%d%d",&u,&v);

              add(u,v);

              add(v,u);

            }

         dfs(,);

         printf("%d\n",tot[]%mod);

     }

     return ;

 }