#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ld long double
#define show(x,y) cout << y << " " << #x << endl;
#define show2(x,y,i,j) cout << y << " " << #x << " " << j << " " << #i << endl;
#define show3(x,y,i,j,p,q) cout << y << " " << #x << " " << j << " " << #i << " " << q << " " << #p << endl;
#define show4(x,y) for(auto it:x) cout << it << " "; cout << #y << endl;
typedef pair<long long,long long>pii;
inline pii combine(pii a, pii b){
return {min(a.first,b.first),max(a.second,b.second)};
}
struct node{
int s,e,m;
node *l,*r;
pii v; //mini maxi
int lazyMin,lazyMax;
node(int ss, int ee):s(ss),e(ee),m((s+e)>>1){
v={s,e};
lazyMin=INT_MAX;
lazyMax=INT_MIN;
if(s!=e){
l=new node(s,m);
r=new node(m+1,e);
v=combine(l->v,r->v);
}
}
void self_min(int x){
v.first=min(v.first,x);
lazyMin=min(lazyMin,x);
}
void self_max(int x){
v.second=max(v.second,x);
lazyMax=max(lazyMax,x);
}
void forceProp(){
if(s==e) return;
l->self_min(lazyMin); r->self_min(lazyMin);
l->self_max(lazyMax); r->self_max(lazyMax);
}
void rangeUpd(int x, int y, pii c){
if(x<=s&&y>=e){
self_min(c.first);
self_max(c.second);
return;
}
forceProp();
if(x<=m)l->rangeUpd(x,y,c);
if(y>m)r->rangeUpd(x,y,c);
v=combine(l->v,r->v);
}
pii query(int x, int y){
if(x<=s&&y>=e){
return v;
}
forceProp();
if(y<=m)return l->query(x,y);
if(x>m)return r->query(x,y);
return combine(l->query(x,m),r->query(m+1,y));
}
}*st[20];
void solve(){
int n,k;
cin >> n >> k;
int m;
cin >> m;
for(int x=0;x<20;x++){
st[x]=new node(0,n+5);
}
int temp,temp2;
for(int x=0;x<m;x++){
cin >> temp >> temp2;
if(temp<temp2){
int hold=min(temp+k-1,temp2);
st[0]->rangeUpd(temp,hold,{temp2,temp2});
}
else{
int hold=max(temp-k+1,temp2);
st[0]->rangeUpd(hold,temp,{temp2,temp2});
}
}
pii two[20][n+5];
for(int bit=0;bit<20;bit++){
for(int x=0;x<=n;x++){
if(bit==0){
two[bit][x]=st[bit]->query(x,x);
}
else{
two[bit][x]=st[bit-1]->query(two[bit-1][x].first,two[bit-1][x].second);
st[bit]->rangeUpd(x,x,two[bit][x]);
//show2(bit,bit,x,x);
//show2(l,two[bit][x].first,r,two[bit][x].second);
//show2(prev,two[bit-1][x].first,prev,two[bit-1][x].second);
}
}
}
int q;
cin >> q;
for(int x=0;x<q;x++){
cin >> temp >> temp2;
if(temp<temp2){
int l=temp;
int r=temp;
int ans=0;
for(int bit=19;bit>=0;bit--){
pii hold=st[bit]->query(l,r);
if(hold.second<temp2){
ans+=1<<bit;
l=hold.first;
r=hold.second;
}
}
if(st[0]->query(l,r).second<temp2){
cout << -1 << "\n";
}
else{
cout << ans+1 << "\n";
}
}
else{
int l=temp;
int r=temp;
int ans=0;
for(int bit=19;bit>=0;bit--){
pii hold=st[bit]->query(l,r);
if(hold.first>temp2){
ans+=1<<bit;
l=hold.first;
r=hold.second;
}
}
if(st[0]->query(l,r).first>temp2){
cout << -1 << "\n";
}
else{
cout << ans+1 << "\n";
}
}
}
}
int32_t main(){
ios::sync_with_stdio(0);
cin.tie(0);
int t=1;
//cin >> t;
while(t--){
solve();
}
}
