#include<bits/stdc++.h>
using namespace std;
const int N = 1e5;
const int Q = 5e4;
const int logN = 20;
vector <int> op[N + 1];
multiset <int> s;
int l[N][logN],r[N][logN];
int segl[N*4],segr[N*4];
int q1[Q],q2[Q];
int ql1[Q],qr1[Q];
int ans[Q];
int n,k,m,q;
void build(int l2, int r2, int id, int node = 1){
if(l2 == r2){
segl[node] = l[l2][id];
segr[node] = r[l2][id];
}else{
int mij = (l2 + r2)/2;
build(l2, mij, id, node*2);
build(mij + 1, r2, id, node*2 + 1);
segl[node] = min(segl[node*2],segl[node*2 + 1]);
segr[node] = max(segr[node*2],segr[node*2 + 1]);
}
}
pair<int,int> query(int ql, int qr, int l2 = 0, int r2 = n - 1, int node = 1){
if(ql <= l2 && r2 <= qr){
return {segl[node],segr[node]};
}else{
int mij = (l2 + r2)/2;
if(qr <= mij){
return query(ql, qr, l2, mij, node*2);
}else if(mij + 1 <= ql){
return query(ql, qr, mij + 1, r2, node*2 + 1);
}else{
auto x = query(ql, qr, l2, mij, node*2);
auto y = query(ql, qr, mij + 1, r2, node*2 + 1);
return {min(x.first,y.first),max(x.second,y.second)};
}
}
}
int main(){
cin>>n>>k;
cin>>m;
for(int i = 0;i < m;i++){
int a,b;
cin>>a>>b;
a--;b--;
if(a < b){
op[a].push_back(b + 1);
op[min(a + k,b)].push_back(-(b + 1));
}else{
op[max(a - k + 1,b + 1)].push_back(b + 1);
op[a + 1].push_back(-(b + 1));
}
}
for(int i = 0;i < n;i++){
for(auto j:op[i]){
if(j > 0){
s.insert(j - 1);
}else{
s.erase(s.find(-j - 1));
}
}
s.insert(i);
l[i][0] = *s.begin();
r[i][0] = *s.rbegin();
s.erase(s.find(i));
}
for(int j = 1;j < logN;j++){
///nlog^2n im crying and shaking rn
build(0, n - 1, j - 1);
for(int i = 0;i < n;i++){
auto x = query(l[i][j - 1],r[i][j - 1]);
l[i][j] = x.first;
r[i][j] = x.second;
}
}
///PBS lesgooooooooo
cin>>q;
for(int i = 0;i < q;i++){
cin>>q1[i]>>q2[i];
q1[i]--;
q2[i]--;
ql1[i] = qr1[i] = q1[i];
ans[i] = 1;
}
for(int j = logN - 1;j >= 0;j--){
build(0,n - 1,j);
for(int i = 0;i < q;i++){
auto x = query(ql1[i],qr1[i]);
if(!(x.first <= q2[i] && q2[i] <= x.second)){
ql1[i] = x.first;
qr1[i] = x.second;
ans[i]+=(1<<j);
}
}
}
for(int i = 0;i < q;i++){
if(ans[i] == (1<<logN))ans[i] = -1;
cout<<ans[i]<<'\n';
}
return 0;
}
