#include <bits/stdc++.h>
#define rep(i,j,k) for(int i=(j);i<=(k);i++)
#define per(i,j,k) for(int i=(j);i>=(k);i--)
#define uint unsigned int
#define ll long long
#define ull unsigned long long
#define db double
#define ldb long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define mkp make_pair
#define eb emplace_back
#define SZ(S) (int)S.size()
//#define mod 998244353
//#define mod 1000000007
#define inf 0x3f3f3f3f
#define linf 0x3f3f3f3f3f3f3f3f
using namespace std;

template <class T>
void chkmax(T &x,T y){
	if(x < y) x = y;
}

template <class T>
void chkmin(T &x,T y){
	if(x > y) x = y;
}

inline int popcnt(int x){
	return __builtin_popcount(x);
}

inline int ctz(int x){
	return __builtin_ctz(x);
}


/*ll power(ll p,int k = mod - 2){
	ll ans = 1;
	while(k){
		if(k % 2 == 1) ans = ans * p % mod;
		p = p * p % mod;
		k /= 2;	
	}
	return ans;
}*/
int n,m;

int cnt;
int head[200005];
struct eg{
	int to,nxt;
}edge[400005];

void make(int u,int v){
	edge[++cnt].to = v;
	edge[cnt].nxt = head[u];
	head[u] = cnt;
}

int N,fa[200005],siz[200005],dfn[200005],dep[200005],ST[20][200005];
inline int cmp(int x,int y){
	if(dep[x] < dep[y]) return x;
	return y;
}
inline int qry(int l,int r){
	int x = __lg(r - l + 1);
	return cmp(ST[x][l],ST[x][r - (1 << x) + 1]);
}
inline int LCA(int u,int v){
	if(u == v) return u;
	u = dfn[u];v = dfn[v];
	if(u > v) swap(u,v);
	return fa[qry(u + 1,v)];
}
void dfs(int u,int f){
	siz[u] = 1;
	dfn[u] = ++N;
	dep[u] = dep[f] + 1;
	fa[u] = f;
	ST[0][N] = u;
	for(int i = head[u];i;i = edge[i].nxt){
		int v = edge[i].to;
		if(v == f) continue;
		dfs(v,u);
		siz[u] += siz[v];
	}
}
int tree[200005];
#define lowbit(x) (x & (-x))
void upd(int pos,int C){
	while(pos <= n){
		tree[pos] += C;
		pos += lowbit(pos);
	}
}

int qry(int pos){
	int res = 0;
	while(pos){
		res += tree[pos];
		pos -= lowbit(pos);
	}
	return res;
}

int cov[200005];
void mdf(int u,int C){
	upd(dfn[u],C);
	if(dfn[u] + siz[u] <= n) upd(dfn[u] + siz[u],-C);
}

int chainsum(int u,int v,int d){
	return qry(dfn[u]) + qry(dfn[v]) - 2 * qry(dfn[d]) + cov[d];
}

void cover(int u){
	if(cov[u]) return;
	cov[u] = 1;
	mdf(u,1);
}

void dcover(int u){
	if(!cov[u]) return;
	cov[u] = 0;
	mdf(u,-1);
}

int idx[200005];
struct path{
	int u,v,d;
}S[200005];
bool cmp2(path p,path q){
	return dep[p.d] > dep[q.d];
}

int solve(int k){
	rep(i,1,k) cover(idx[i]);
	rep(i,1,k - 1){
		S[i].u = idx[i];S[i].v = idx[i + 1];S[i].d = LCA(idx[i],idx[i + 1]);
//		printf("%d ",S[i].d);
	}
//	printf("\n");
	sort(S + 1,S + k,cmp2);
	int ans = 0;
	rep(i,1,k - 1){
		if(chainsum(S[i].u,S[i].v,S[i].d) == 2){
			cover(S[i].d);
		}else{
			ans++;
		}
	}
	rep(i,1,k) dcover(idx[i]);
	rep(i,1,k - 1) dcover(S[i].d);
	return ans;
}

int main(){
//	freopen("test.in","r",stdin);
	scanf("%d%d",&n,&m);
	rep(i,1,n - 1){
		int u,v;
		scanf("%d%d",&u,&v);
		make(u,v);make(v,u);
	}
	dfs(1,0);
	rep(i,1,17){
		rep(j,1,n){
			if(j + (1 << i) - 1 > n) break;
			ST[i][j] = cmp(ST[i - 1][j],ST[i - 1][j + (1 << (i - 1))]);
		}
	}

	rep(i,1,m){
		int sz;
		scanf("%d",&sz);
		rep(j,1,sz) scanf("%d",&idx[j]);
		printf("%d\n",solve(sz));
	}
	return 0;
}