#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
int n, k; cin >> n >> k;
int l[n + 5], r[n + 5];
iota(l + 1, l + n + 1, 1);
iota(r + 1, r + n + 1, 1);
int m; cin >> m;
vector<int> add[n + 5], del[n + 5];
int a[m + 5], b[m + 5];
for(int i = 1; i <= m; i++){
cin >> a[i] >> b[i];
if(a[i] < b[i]){
add[a[i]].push_back(b[i]);
del[min(a[i] + k - 1, b[i] - 1)].push_back(b[i]);
}
}
multiset<int, greater<int> > st;
for(int i = 1; i <= n; i++){
for(int j : add[i]) st.insert(j);
if(!st.empty()) r[i] = *st.begin();
for(int j:del[i]) st.erase(st.find(j));
add[i].clear();
del[i].clear();
}
for(int i = 1; i <= m; i++){
if(a[i] > b[i]){
add[a[i]].push_back(b[i]);
del[max(a[i] - k + 1, b[i] + 1)].push_back(b[i]);
}
}
st.clear();
multiset<int> st2;
for(int i = n; i >= 1; i--){
for(int j : add[i]) st2.insert(j);
if(!st2.empty()) l[i]=*st2.begin();
for(int j:del[i]) st2.erase(st2.find(j));
}
int q; cin >> q;
while(q--){
int s, t; cin >> s >> t;
int ans = -1, cur = 0, L = s, R = s;
vector<int>v;
v.push_back(s);
while(!v.empty()){
int Li = L, Ri = R;
for(int i : v){
Li = min(Li, l[i]);
Ri = max(Ri, r[i]);
if(i == t){
ans = cur;
break;
}
}
if(ans > -1) break;
v.clear();
for(int i = Li; i < L; i++) v.push_back(i);
for(int i = Ri; i > R; i--) v.push_back(i);
L = Li;
R = Ri;
cur++;
}
cout << ans << '\n';
}
}
