#include<bits/stdc++.h>
#define int long long
using namespace std;

const int N=102;
const int P=(1<<61)-1;

int n,m,V,q;
int ans[N][N],l[N];
bool vis[N];

vector<int> g[N];
vector<int> d[N];

void dfs(int host,int num){
    vis[num]=1;ans[host][num]=max(ans[host][num],l[num]);
    for(int i=0;i<g[num].size();i++){
        int u=g[num][i],w=d[num][i];
        if(vis[u]) continue;
        l[u]=l[num] & w;
        dfs(host,u);
    }
    vis[num]=0;
}
signed main()
{
    freopen("Paths.in","r",stdin);
    freopen("Paths.out","w",stdout);
    cin>>n>>m>>q>>V;
    for(int i=1;i<=m;i++){
        int u,v,w;
        cin>>u>>v>>w;
        g[u].push_back(v);d[u].push_back(w);
        g[v].push_back(u);d[v].push_back(w);
    }
    
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            ans[i][j]=l[j]=-1;
        }
        l[i]=P;
        dfs(i,i);
        ans[i][i]=0;
    }
    while(q--){
        int u,v;cin>>u>>v;
        if(ans[u][v]>=V) cout<<"Yes"<<endl;
        else cout<<"No"<<endl;
    }
    return 0;
 }