#include<iostream>
#include<cstdio>
#include<vector>
#include<algorithm>
#define N 400000
using namespace std;
const int inf=(int)(1e9);
int read()
{
	char c=0;
	int sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
struct rds
{
	int num,data;
	bool operator < (const rds &t)const
    {
 		return data<t.data;	
	}
};
int c,n,m,q,rt,cater,sdepth[N+1],fa[N+1][21],a[N+1],cl[N+1],maxp[N+1],smz,szt[N+1],lg[N+1],depth[N+1],dfn[N+1],leng,rev[N+1],sz[N+1],X[N+1],Y[N+1],tong[N+1],ps[N+1],ST[N+1][21],ans[N+1],dque[N+1],top,length;
bool used[N+1],vis[N+1];
vector<int>E[N+1];
vector<int>ES[N+1];
vector<int>p[N+1];
vector<rds>v[N+1];
vector<int>A[N+1];
vector<rds>B[N+1];
void add(int x,int y)
{
	E[x].push_back(y),E[y].push_back(x);
	return;
}
void dfs(int x)
{
	dfn[x]=++leng,rev[dfn[x]]=x,sz[x]=1,tong[++length]=dfn[x],ps[x]=length;
	for (int i=0;i<E[x].size();++i)
		if (!dfn[E[x][i]])
			depth[E[x][i]]=depth[x]+1,dfs(E[x][i]),fa[E[x][i]][0]=x,sz[x]+=sz[E[x][i]],tong[++length]=dfn[x];
	return;
}
bool LENG(int x,int y)
{
	return dfn[x]<=dfn[y]&&dfn[y]<=dfn[x]+sz[x]-1;
}
int lca(int x,int y)
{
	x=ps[x],y=ps[y];
	if (x>y) swap(x,y);
    int lw=lg[y-x];
	return rev[min(ST[x][lw],ST[y-(1<<lw)+1][lw])];
}
int dis(int x,int y)
{
	return depth[x]+depth[y]-(depth[lca(x,y)]<<1);
}
int get_mid(int x,int y)
{
	int d=dis(x,y)>>1;
	if (depth[x]<depth[y]) swap(x,y);
	for (int i=lg[d];i>=0;--i)
		if ((d>>i)&1)
			x=fa[x][i];
	return x;
}
bool cmp(int x,int y)
{
	return dfn[x]<dfn[y];
}
struct reads
{
	int x,y;
};
reads zero,ST2[N+1][21];
int num[4];
reads operator + (reads a,reads b)
{
	if (!a.x) return b;
	if (!b.x) return a;
	int res=-inf,x=0,y=0;
	num[0]=a.x,num[1]=a.y,num[2]=b.x,num[3]=b.y;
	for (int i=0;i<=3;++i)
		for (int j=i+1;j<=3;++j)
			if (dis(num[i],num[j])>res)
				res=dis(num[i],num[j]),x=num[i],y=num[j];
	return (reads){x,y};
}
reads query(int l,int r)
{
	if (l>r) return zero;
	int lw=lg[r-l+1];
	return ST2[l][lw]+ST2[r-(1<<lw)+1][lw];
}
void dfs2(int x)
{
	reads d=zero;
	if (ES[x].empty()) d=d+query(dfn[x],dfn[x]+sz[x]-1);
	for (int i=0;i<ES[x].size();++i)
	{
		if (!i) d=d+query(dfn[x],dfn[ES[x][i]]-2);
		else d=d+query(dfn[ES[x][i-1]]+sz[ES[x][i-1]],dfn[ES[x][i]]-2);
		if (i+1==ES[x].size()) d=d+query(dfn[ES[x][i]]+sz[ES[x][i]],dfn[x]+sz[x]-1);
    }
	p[get_mid(d.x,d.y)].push_back(dis(d.x,d.y)>>1);
	for (int i=0;i<ES[x].size();++i) dfs2(ES[x][i]);
	ES[x].clear(),ES[x].shrink_to_fit();
	return;
}
void get_rt(int x)
{
	vis[x]=szt[x]=1,maxp[x]=0;
	for (int i=0;i<E[x].size();++i)
		if (!used[E[x][i]]&&!vis[E[x][i]])
			get_rt(E[x][i]),maxp[x]=max(maxp[x],szt[E[x][i]]),szt[x]+=szt[E[x][i]];
	maxp[x]=max(maxp[x],smz-szt[x]);
	if (maxp[x]<maxp[rt]) rt=x;
	vis[x]=0;
	return;
}
void dfs3(int x)
{
	vis[x]=szt[x]=1;
	if (x==rt) cl[x]=++cater;
	for (int i=0;i<p[x].size();++i)
	{
		A[1].push_back(p[x][i]+sdepth[x]);
		if (x!=rt) A[cl[x]].push_back(p[x][i]+sdepth[x]);
	}
	for (int i=0;i<v[x].size();++i)
	{
		B[1].push_back((rds){v[x][i].num,v[x][i].data-sdepth[x]});
		if (x!=rt) B[cl[x]].push_back((rds){v[x][i].num,v[x][i].data-sdepth[x]});
	}
	vis[x]=1;
	for (int i=0;i<E[x].size();++i)
		if (!used[E[x][i]]&&!vis[E[x][i]])
		{
			sdepth[E[x][i]]=sdepth[x]+1;
			if (x==rt) cl[E[x][i]]=++cater;
			else cl[E[x][i]]=cl[x];
			dfs3(E[x][i]),szt[x]+=szt[E[x][i]];
		}
	vis[x]=0;
	return;
}
void solve(int x)
{
	int ps;
	cater=0,used[x]=1,sdepth[x]=0,dfs3(x);
	for (int i=1;i<=cater;++i)
	{
		sort(A[i].begin(),A[i].end()),sort(B[i].begin(),B[i].end());
		if (i==1)
		{
			ps=-1;
			for (int j=0;j<B[i].size();++j)
			{
				while (ps+1<A[i].size()&&A[i][ps+1]<=B[i][j].data) ++ps;
				ans[B[i][j].num]+=ps+1;
			}
		}
		else
		{
			ps=-1;
			for (int j=0;j<B[i].size();++j)
			{
				while (ps+1<A[i].size()&&A[i][ps+1]<=B[i][j].data) ++ps;
				ans[B[i][j].num]-=ps+1;
			}
		}
		A[i].clear(),A[i].shrink_to_fit(),B[i].clear(),B[i].shrink_to_fit();
	}
	for (int i=0;i<E[x].size();++i)
		if (!used[E[x][i]])
			smz=szt[E[x][i]],rt=0,get_rt(E[x][i]),solve(rt);
	return;
}
int main()
{
	int x,d,k;
	for (int i=2;i<=N;++i) lg[i]=lg[i>>1]+1;
	c=read(),n=read(),m=read(),q=read(),maxp[0]=inf;
	for (int i=1;i<=n-1;++i) X[i]=read(),Y[i]=read(),add(X[i],n+i),add(Y[i],n+i);
	depth[1]=1,dfs(1);
	for (int i=1;i<=length;++i) ST[i][0]=tong[i];
	for (int i=1;i<=lg[length];++i)
		for (int j=1;j+(1<<i)-1<=length;++j)
			ST[j][i]=min(ST[j][i-1],ST[j+(1<<(i-1))][i-1]);
	for (int i=1;i<=(n<<1)-1;++i) ST2[i][0]=(reads){rev[i],rev[i]};
	for (int i=1;i<=lg[(n<<1)-1];++i)
		for (int j=1;j+(1<<i)-1<=(n<<1)-1;++j)
			fa[j][i]=fa[fa[j][i-1]][i-1],ST2[j][i]=ST2[j][i-1]+ST2[j+(1<<(i-1))][i-1];
	while (m--)
	{
		k=read(),top=0;
		for (int i=1;i<=k;++i)
		{
			x=read();
			if (depth[X[x]]<depth[Y[x]]) a[i]=Y[x];
			else a[i]=X[x];
		}
		a[++k]=1,sort(a+1,a+k+1,cmp);
		for (int i=1;i<=k;++i)
		{
			while (top&&!LENG(dque[top],a[i])) top--;
			if (top) ES[dque[top]].push_back(a[i]);
			dque[++top]=a[i];
		}
		dfs2(1);
	}
	for (int i=1;i<=q;++i) x=read(),d=read()<<1,v[x].push_back((rds){i,d});
	for (int i=1;i<=(n<<1)-1;++i) used[i]=0;
	smz=n,get_rt(1),solve(rt);
	for (int i=1;i<=q;++i) printf("%d\n",ans[i]);
	return 0;
}