#include <iostream>
  
#include <queue>
  
#include <vector>
  
using namespace std;
  
bool vis[10005];
  
vector<int>workernet[10005];
  
int n , m , q;
  
bool BFS(int a , int L);
  
int main() {
  
    cin >> n >> m >> q;
  
    for(int i = 0; i < m; i++) {
                         
        int u , v;
                         
        cin >> u >> v;
  
        workernet[u].push_back(v);
  
        workernet[v].push_back(u);
  
    }
  
    for(int i = 0; i < q; i++) {
                         
        int a , L;
                         
        cin >> a >> L;
  
        bool xuanusedflag = BFS(a , L);
  
        if(xuanusedflag) {
  
            cout << "Yes" << endl;
  
            continue;
  
        } else {
  
            cout << "No" << endl;
  
        }
  
    }
  
}
  
bool BFS(int a , int L) {
  
    queue<int>neededworkers;
  
    neededworkers.push(a);
  
    while(!neededworkers.empty()) {
  
        for(int i = 0; i < workernet[neededworkers.front()].size(); i++) {
                                                                   
            if(vis[neededworkers.front()][i] == false && neededworkers.front() <= n && i <= n) {
                                                                                             
                neededworkers.push(workernet[neededworkers.front()][i]);
                                                                                             
                vis[neededworkers.front()][i] = true;
                                                                                             
            }
                                                                                             
        }
                                                                                             
        if(neededworkers.front() == 1 && L == 1) {
                                                                                             
            return true;
                                                                                             
        }
                                                                                             
    }
                                                                                             
    return false;
                                                                                             
}