#include<iostream>
using namespace std;

#define ll long long
ll n,m,q,v,a,b,c,cnt,head[100010],par[100010];
bool vis[100010];
struct e
{
    ll to,next,w;
}edge[1000010];

void addedge(int x,int y,int z)
{
    edge[++cnt].to = y;
    edge[cnt].w = z;
    edge[cnt].next = head[x];
    head[x] = cnt;
}

ll find(ll x)
{
    if(x!=par[x])
        par[x] = find(par[x]);
    return par[x];
}

void unionn(ll x,ll y)
{
    int i = find(x);
    int j = find(y);
    if(i!=j)
        par[i] = j;
}

bool dfs(ll x,ll y)
{
    if(y == b)
    {
        if(x>=v)
        {
            puts("Yes");
            return true;
        }
        else
        {
            return false;
        }
    }
    for(int i=head[y];i;i=edge[i].next)
    {
        if(!vis[edge[i].to])
        {
            vis[edge[i].to] = 1;
            bool k = dfs(edge[i].w&x,edge[i].to);
            vis[edge[i].to] = 0;
            if(k)
                return true;
        }
    }
    return false;
}

void solve()
{
    cin>>a>>b;
    if(find(a)!=find(b)){
        puts("No");return;
    }

    vis[a] = 1;
    for(int i=head[a];i;i=edge[i].next)
    {
        vis[edge[i].to] = 1;
        bool k = dfs(edge[i].w,edge[i].to);
        vis[edge[i].to] = 0;
        if(k)
            return;
    }
    puts("No");
    return;
}

int main()
{
    cin>>n>>m>>q>>v;
    for(int i=1;i<=n;i++)
        par[i] = i;
    while(m--)
    {
        cin>>a>>b>>c;
        addedge(a,b,c);
        addedge(b,a,c);
        unionn(a,b);
    }
    while(q--)
    {
        solve();
    }
}