#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MXN = 1e5 + 20 , LOG = 19;
vector<int> adj[MXN];
vector<int> euler;
map<pair<int,int>,int> idx;
int st_time[MXN] , sz[MXN] , p[LOG][MXN] , h[MXN];
int d[MXN] , ans[MXN] , sm[MXN];
int n,m,k;
struct seg_tree {
int size;
vector<int> v;
seg_tree() {
size = 1;
while(size < n) size <<= 1;
v.assign(2*size , 0);
}
void add(int x , int lx , int rx , int i , int k) {
if(rx-lx == 1) {
v[x] += k; return;
}
int m = (lx+rx)/2;
if(i < m) {
add(2*x+1 , lx , m , i , k);
} else {
add(2*x+2 , m , rx , i , k);
}
v[x] = v[2*x+1] + v[2*x+2];
}
void add(int i , int k) {
add(0 , 0 , size , i , k);
}
int sum(int x , int lx , int rx , int l , int r) {
if(lx >= l && rx <= r) {
return v[x];
}
if(lx >= r || rx <= l) {
return 0;
}
int m = (lx+rx)/2;
return sum(2*x+1 , lx , m , l , r) + sum(2*x+2 , m , rx , l , r);
}
int sum(int l , int r) {
return sum(0 , 0 , size , l , r);
}
};
struct fenwick {
vector<int> v;
fenwick() {
v.assign(n , 0);
}
void add(int i , int k) {
for(; i < n ; i = (i|(i+1))) {
v[i] += k;
}
}
int sum(int x) {
if(x < 0) return 0;
int ans = 0;
for(; x >= 0 ; x = (x&(x+1))-1) {
ans += v[x];
}
return ans;
}
int sum(int l , int r) {
return sum(r)-sum(l-1);
}
};
void DFS(int v , int dad) {
euler.push_back(v); st_time[v] = euler.size()-1;
sz[v] = 1;
p[0][v] = (dad == -1 ? v : dad);
h[v] = (dad == -1 ? 0 : h[dad]+1);
for(auto u : adj[v]) {
if(u == dad) continue;
DFS(u , v);
sz[v] += sz[u];
}
}
void final_DFS(int v , int dad) {
int res = d[v];
for(auto u : adj[v]) {
if(u == dad) continue;
final_DFS(u , v);
res += sm[u];
}
sm[v] = res;
if(dad != -1) ans[idx[{v , dad}]] = res;
}
void build_LCA() {
for(int i = 1 ; i < LOG ; i++) {
for(int j = 1 ; j <= n ; j++) {
p[i][j] = p[i-1][p[i-1][j]];
}
}
}
int kth_anc(int k , int v) {
while(k > 0) {
int x = __builtin_ctz(k);
v = p[x][v];
k -= (1 << x);
}
return v;
}
int LCA(int v , int u) {
if(h[v] > h[u]) swap(v,u);
u = kth_anc(h[u]-h[v] , u);
if(u == v) return v;
for(int i = LOG-1 ; i >= 0 ; i--) {
if(p[i][v] != p[i][u]) {
v = p[i][v]; u = p[i][u];
}
}
return p[0][v];
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(NULL);
cin >> n >> m >> k;
for(int i = 1 ; i < n ; i++) {
int v,u; cin >> v >> u;
adj[v].push_back(u); adj[u].push_back(v);
idx[{v , u}] = i; idx[{u , v}] = i;
}
DFS(1 , -1);
build_LCA();
for(int q = 0 ; q < m ; q++) {
fenwick fen;
int s; cin >> s;
int v,u; cin >> v >> u;
int lca = LCA(v , u);
d[v]++; d[u]++; d[lca] -= 2;
fen.add(st_time[v] , 1); fen.add(st_time[u] , 1);
v = lca;
for(int i = 2 ; i < s ; i++) {
int u; cin >> u;
lca = LCA(v , u);
if(lca != v) {
d[u]++; d[v]++; d[lca] -= 2;
fen.add(st_time[u] , 1);
} else {
if(fen.sum(st_time[u] , st_time[u]+sz[u]-1) > 0) continue;
int _u = u;
for(int i = LOG-1 ; i >= 0 ; i--) {
int par = p[i][_u];
if(par != 1 && fen.sum(st_time[par] , st_time[par]+sz[par]-1) <= 0) {
_u = par;
}
}
_u = p[0][_u];
d[u]++; d[_u]--;
fen.add(st_time[u] , 1);
}
v = lca;
}
}
final_DFS(1 , -1);
vector<int> res;
for(int i = 1 ; i < n ; i++) {
if(ans[i] >= k) res.push_back(i);
}
cout << res.size() << "\n";
for(auto u : res) {
cout << u << " ";
}
cout << "\n";
}
