#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 + 10;
const int MAXQ = 5e4 + 10;
vector<int> adj[MAXN];
int dist[MAXN], marc[MAXN];
int n, k;
vector<pair<int, int>> pre[MAXN], nxt[MAXN];
void bfs(int x){
set<int> s;
for(int i=1; i<=n; i++){
dist[i] = 1e9;
marc[i] = 0;
s.insert(i);
}
queue<int> q;
marc[x] = 1;
dist[x] = 0;
q.push(x);
s.erase(x);
while(!q.empty()){
int v = q.front();
q.pop();
for(auto u : adj[v]){
vector<int> to_erase;
if(v < u){
auto w = s.upper_bound(v);
while(w != s.end() && *w <= u){
dist[*w] = dist[v] + 1;
marc[*w] = 1;
q.push(*w);
to_erase.push_back(*w);
++ w;
}
} else{
auto w = s.lower_bound(u);
while(w != s.end() && *w < v){
dist[*w] = dist[v] + 1;
marc[*w] = 1;
q.push(*w);
to_erase.push_back(*w);
++ w;
}
}
for(auto x : to_erase) s.erase(x);
}
}
}
int main(){
cin.tie(0)->sync_with_stdio(0);
cin >> n >> k;
int cur = n;
int m; cin >> m;
while(m--){
int a, b; cin >> a >> b;
if(a < b){
nxt[a].push_back({b, 1});
nxt[min(b + 1, a + k)].push_back({b, -1});
} else{
pre[a].push_back({b, 1});
pre[max(b - 1, a - k)].push_back({b, -1});
}
}
multiset<int> ms;
for(int i=1; i<=n; i++){
for(auto j : nxt[i]){
if(j.second == -1){
ms.erase(ms.find(j.first));
} else ms.insert(j.first);
}
if(!ms.empty()) adj[i].push_back(*ms.rbegin());
}
ms.clear();
for(int i=n; i>=1; i--){
for(auto j : pre[i]){
if(j.second == -1){
ms.erase(ms.find(j.first));
} else ms.insert(j.first);
}
if(!ms.empty()) adj[i].push_back(*ms.begin());
}
/*for(int i=1; i<=n; i++){
cout << i << ": ";
for(auto j : adj[i]) cout << j << " ";
cout << "\n";
}*/
int q; cin >> q;
while(q--){
int a, b; cin >> a >> b;
bfs(a);
cout << (marc[b] ? dist[b] : -1) << "\n";
}
return 0;
}
