#include<bits/stdc++.h>
using namespace std;
const int K = 17;
const int nx = 1e5;
int spx[K][K][nx+1], spm[K][K][nx+1];
int d[nx+1];
int qux(int l, int r, int k){
int dif = 31-__builtin_clz(r-l+1);
return max(spx[k][dif][l], spx[k][dif][r-(1<<dif)+1]);
}
int qum(int l, int r, int k){
int dif = 31-__builtin_clz(r-l+1);
return min(spm[k][dif][l], spm[k][dif][r-(1<<dif)+1]);
}
void solve(){
int n, k, m;cin >> n >> k >> m;
int lr[n+1] = {0}, rl[n+1];
int L[n+1], R[n+1];
fill(rl, rl+n+1, n+1);
while(m--){
int a, b;cin >> a >> b;
if(a < b) lr[a] = max(lr[a], b);
else rl[a] = min(rl[a], b);
}
multiset<int> ms;
for(int i = 1;i <= n;i++){
ms.insert(lr[i]);
if(i>k) ms.erase(ms.find(lr[i-k]));
R[i] = max(*ms.rbegin(), i);
spx[0][0][i] = R[i];
}
ms.clear();
for(int i = n;i;i--){
ms.insert(rl[i]);
if(i+k<=n) ms.erase(ms.find(rl[i+k]));
L[i] = min(*ms.begin(), i);
spm[0][0][i] = L[i];
}
for(int v = 1;v < K;v++){
for(int i = 1;i+(1<<v)-1 <= n;i++){
spx[0][v][i] = max(spx[0][v-1][i], spx[0][v-1][i+(1<<v-1)]);
spm[0][v][i] = min(spm[0][v-1][i], spm[0][v-1][i+(1<<v-1)]);
}
}
for(int V = 1;V < K;V++){
for(int i = 1;i <= n;i++){
spx[V][0][i] = qux(spm[V-1][0][i], spx[V-1][0][i], V-1);
spm[V][0][i] = qum(spm[V-1][0][i], spx[V-1][0][i], V-1);
}
for(int v = 1;v < K;v++){
for(int i = 1;i+(1<<v)-1 <= n;i++){
spx[V][v][i] = max(spx[V][v-1][i], spx[V][v-1][i+(1<<v-1)]);
spm[V][v][i] = min(spm[V][v-1][i], spm[V][v-1][i+(1<<v-1)]);
}
}
}
int q;cin >> q;
while(q--){
int s, t;cin >> s >> t;
int ans = 0;
int Ls = s, Rs = s;
for(int i = K-1;i >= 0;i--){
if(qum(Ls, Rs, i) > t || qux(Ls, Rs, i) < t){
ans |= 1<<i;
int ols = Ls;
Ls = qum(Ls, Rs, i);
Rs = qux(ols, Rs, i);
}
}
if(qum(Ls, Rs, 0) <= t && qux(Ls, Rs, 0) >= t) cout << ans+1 << '\n';
else cout << "-1\n";
}
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
solve();
}
