#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N=1e5+5;
int n,k,m,q,lim;
int stl[N][25],str[N][25],fl[N][25],fr[N][25],lf[N],rt[N];
int lmn[N],lmx[N],rmn[N],rmx[N];
int Min(int a,int b){return lf[a]<lf[b]?a:b;}
int Max(int a,int b){return rt[a]>rt[b]?a:b;}
int queryl(int l,int r){
int lg=std::__lg(r-l+1);
return min(stl[l][lg],stl[r-(1<<lg)+1][lg]);
}
int queryr(int l,int r){
int lg=std::__lg(r-l+1);
return max(str[l][lg],str[r-(1<<lg)+1][lg]);
}
int queryL(int l,int r){
int lg=std::__lg(r-l+1);
return Min(stl[l][lg],stl[r-(1<<lg)+1][lg]);
}
int queryR(int l,int r){
int lg=std::__lg(r-l+1);
return Max(str[l][lg],str[r-(1<<lg)+1][lg]);
}
void query(int s,int t){
int l=s,r=s,res=1;
if(lf[s]>t||rt[s]<t){
for(int j=lim;j>=0;j--){
int L=Min(Min(fl[lmn[l]][j],fl[rmn[r]][j]),Min(fl[lmx[l]][j],fl[rmx[r]][j]));
int R=Max(Max(fr[lmn[l]][j],fr[rmn[r]][j]),Max(fr[lmx[l]][j],fr[rmx[r]][j]));
if(lf[L]>t||rt[R]<t) l=L,r=R,res+=(1<<j);
}
res++;
}
cout<<(res>n?-1:res)<<"\n";
}
signed main(){
std::ios::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
cin>>n>>k>>m;
memset(stl,0x3f,sizeof(stl));
for(int i=1,a,b;i<=m;i++){
cin>>a>>b;
if(a>b) stl[a][0]=min(stl[a][0],b);
else str[a][0]=max(str[a][0],b);
}
for(int j=1;(1<<j)<=n;j++)
for(int i=1;i+(1<<j)-1<=n;i++){
stl[i][j]=min(stl[i][j-1],stl[i+(1<<(j-1))][j-1]);
str[i][j]=max(str[i][j-1],str[i+(1<<(j-1))][j-1]);
}
for(int i=1;i<=n;i++){
lf[i]=min(i,queryl(i,min(i+k-1,n)));
rt[i]=max(i,queryr(max(i-k+1,1),i));
stl[i][0]=str[i][0]=i;
}
for(int j=1;(1<<j)<=n;j++)
for(int i=1;i+(1<<j)-1<=n;i++){
stl[i][j]=Min(stl[i][j-1],stl[i+(1<<(j-1))][j-1]);
str[i][j]=Max(str[i][j-1],str[i+(1<<(j-1))][j-1]);
}
for(int i=1;i<=n;i++){
fl[i][0]=fr[i][0]=i;
lmn[i]=min(i,queryL(lf[i],i));
lmx[i]=max(i,queryR(lf[i],i));
rmn[i]=min(i,queryL(i,rt[i]));
rmx[i]=max(i,queryR(i,rt[i]));
}
for(int j=1;(1<<j)<=n;j++,lim++){
for(int i=1;i<=n;i++){
int l=fl[i][j-1],r=fr[i][j-1];
fl[i][j]=Min(Min(fl[lmn[l]][j-1],fl[rmn[r]][j-1]),Min(fl[lmx[l]][j-1],fl[rmx[r]][j-1]));
fr[i][j]=Max(Max(fr[lmn[l]][j-1],fr[rmn[r]][j-1]),Max(fr[lmx[l]][j-1],fr[rmx[r]][j-1]));
// cout<<fl[i][j]<<" "<<fr[i][j]<<"\n";
}
}
cin >>q;
while(q--){
int s , t; cin >> s >> t;
query(s,t);
}
return 0;
}
//ggghurjv
