#pragma GCC optimize("O3")
#include <bits/stdc++.h>
const int LOGN = 20;
const int MAXN = 1e5 + 1;
int up_max[MAXN][LOGN];
int up_min[MAXN][LOGN];
struct SegTree{
int n;
std::vector<std::pair<int,int>> t;
SegTree(int n):n(n){
t.resize(4 * n,{-1,-1});
}
void upd(int i,int l,int r,int pos,int pos1,int x){
if(l == r - 1){
t[i].first = x;
t[i].second = pos1;
return;
}
int mid = (l + r) / 2;
if(pos >= mid){
upd(2 * i + 2,mid,r,pos,pos1,x);
}else{
upd(2 * i + 1,l,mid,pos,pos1,x);
}
t[i] = std::max(t[2 * i + 1],t[2 * i + 2]);
}
std::pair<int,int> query(int i,int l,int r,int ql,int qr){
if(l>=ql && r <= qr){
return t[i];
}
if(l >= qr || ql >=r){
return {-1,-1};
}
int mid = (l + r) / 2;
return std::max(query(2 * i + 1,l,mid,ql,qr),
query(2 *i + 2,mid,r,ql,qr));
}
};
signed main(){
int n,k,m;
std::cin>>n>>k>>m;
SegTree t(n);
std::vector<std::pair<int,int>> all(m);
for(int i =0 ;i < m;i++){
std::cin>>all[i].first>>all[i].second;
all[i].first--;
all[i].second--;
t.upd(0,0,n,all[i].first,i,all[i].second);
}
for(int i = 0;i < m;i++){
auto now = t.query(0,0,n,all[i].first,all[i].second +1);
if(now.first > all[i].second){
up_max[i][0] = now.second;
}else{
up_max[i][0] = i;
}
// std::cout<<i<<' '<<now.second<<std::endl;
}
for(int j =1;j < LOGN;j++){
for(int i = 0;i < m;i++){
up_max[i][j] = up_max[up_max[i][j - 1]][j - 1];
}
}
int q;
std::cin>>q;
while(q--){
int start,stop;
std::cin>>start>>stop;
start--;
stop--;
int left = start - k + 1;
int right = start;
auto now = t.query(0,0,n,left,right + 1);
int tmp = now.second;
if(now.second == -1){
std::cout<<-1<<std::endl;
continue;
}
if(stop <= now.first){
std::cout<<1<<std::endl;
continue;
}
// std::cout<<left<<' '<<right<<"dwhsf; "<<now.second<<std::endl;
int ans = 1;
for(int j = LOGN - 1;j>=0;j--){
// std::cout<<up_max[tmp][j]<<std::endl;
if(all[up_max[tmp][j]].second < stop){
ans += (1<<j);
tmp = up_max[tmp][j];
}
}
if(all[up_max[tmp][0]].second < stop){
std::cout<<-1<<std::endl;
continue;
}
std::cout<<ans + 1<<std::endl;
}
}
