#include<bits/stdc++.h>
#define ri signed
#define pd(i) ++i
#define bq(i) --i
#define func(x) std::function<x>
namespace IO{
    char buf[1<<21],*p1=buf,*p2=buf;
    #define gc() p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<21,stdin),p1==p2)?(-1):*p1++
    #define debug1(x) std::cerr << #x"=" << x << ' '
    #define debug2(x) std::cerr << #x"=" << x << std::endl
    #define Debug(x) assert(x)
    struct nanfeng_stream{
        template<typename T>inline nanfeng_stream &operator>>(T &x) {
            bool f=false;x=0;char ch=gc();
            while(!isdigit(ch)) f|=ch=='-',ch=gc();
            while(isdigit(ch)) x=(x<<1)+(x<<3)+(ch^48),ch=gc();
            return x=f?-x:x,*this;
        }
    }cin;
}
using IO::cin;
namespace nanfeng{
    #define FI FILE *IN
    #define FO FILE *OUT
    template<typename T>inline T cmax(T x,T y) {return x>y?x:y;}
    template<typename T>inline T cmin(T x,T y) {return x>y?y:x;}
    using ll=long long;
    static const int N=2e3+7,MOD=998244353;
    struct edge{int v,nxt;}e[N<<1];
    int first[N],dis[330][330],C[330][330],dep[N],ky[N],U[N],V[N],siz[N],n,m,k,t=1;
    ll res1,res2;
    bool bc[N];
    auto add=[](int u,int v) {
        e[t]={v,first[u]},first[u]=t++;
        e[t]={u,first[v]},first[v]=t++;
    };
    func(void(int,int)) dfs=[](int x,int fa) {
        for (ri i(first[x]),v;i;i=e[i].nxt) {
            if ((v=e[i].v)==fa) continue;
            dep[v]=dep[x]+1;
            dfs(v,x);
        }
    };
    func(void(int,int)) solve=[](int x,int fa) {
        if (bc[x]) siz[x]=1;
        for (ri i(first[x]),v;i;i=e[i].nxt) {
            if ((v=e[i].v)==fa) continue;
            dep[v]=dep[x]+1;
            solve(v,x);
            siz[x]+=siz[v];
        }
    };
    auto fpow=[](int x,int y) {
        int res=1;
        while(y) {
            if (y&1) res=1ll*res*x%MOD;
            x=1ll*x*x%MOD;
            y>>=1;
        }
        return res;
    };
    inline int main() {
        FI=freopen("tree.in","r",stdin);
        FO=freopen("tree.out","w",stdout);
        cin >> n >> m >> k;
        C[0][0]=1;
        for (ri i(1);i<=m;pd(i)) {
            C[i][0]=1;
            for (ri j(1);j<=i;pd(j)) C[i][j]=(C[i-1][j-1]+C[i-1][j])%MOD;
        }
        for (ri i(1);i<=m;pd(i)) cin >> ky[i],bc[ky[i]]=true;
        for (ri i(1);i<n;pd(i)) cin >> U[i] >> V[i],add(U[i],V[i]);
        for (ri i(1);i<=m;pd(i)) {
            dep[ky[i]]=0;
            dfs(ky[i],0);
            for (ri j(1);j<=m;pd(j)) dis[i][j]=dep[ky[j]];
        }
        int al=C[m][k],inv=fpow(al,MOD-2);
        solve(1,0);
        for (ri i(1);i<n;pd(i)) {
            int u=U[i],v=V[i];
            if (dep[u]>dep[v]) std::swap(u,v);
            res1+=1ll*(al-C[siz[v]][k]-C[m-siz[v]][k])*inv%MOD;
        }
        (res1%=MOD)+=MOD;
        (res1*=2)%=MOD;
        for (ri i(1);i<m;pd(i))
            for (ri j(i+1);j<=m;pd(j)) {
                const int len=dis[i][j];
                int cnt=0;
                for (ri k(1);k<=m;pd(k)) {
                    if (i==k||j==k) continue;
                    if (dis[i][k]>len||dis[k][j]>len) continue;
                    if (dis[i][k]==len&&k<j||dis[k][j]==len&&k<i) continue;
                    ++cnt;
                }
                res2+=1ll*C[cnt][k-2]*inv%MOD*len%MOD;
            }
        res2%=MOD;
        printf("%lld\n",(res1-res2+MOD)%MOD);
        return 0;
    }
}
int main() {return nanfeng::main();}