#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define fs first
#define sc second
const int mxn = 1e5+10;
int N,M,K,Q;
pii range[mxn],segtree[mxn*4];
vector<int> lop[mxn],rop[mxn];
void build(int now,int l,int r){
if(l == r){
segtree[now] = range[l];
return;
}
int mid = (l+r)>>1;
build(now*2+1,l,mid);
build(now*2+2,mid+1,r);
segtree[now].fs = min(segtree[now*2+1].fs,segtree[now*2+2].fs);
segtree[now].sc = max(segtree[now*2+1].sc,segtree[now*2+2].sc);
}
pii getval(int now,int l,int r,int s,int e){
if(l>=s&&e>=r)return segtree[now];
int mid = (l+r)>>1;
if(mid>=e)return getval(now*2+1,l,mid,s,e);
else if(mid<s)return getval(now*2+2,mid+1,r,s,e);
else{
auto ta = getval(now*2+1,l,mid,s,e),tb = getval(now*2+2,mid+1,r,s,e);
return make_pair(min(ta.fs,tb.fs),max(ta.sc,tb.sc));
}
}
void solve(){
int s,e;
cin>>s>>e;
pii now = {s,s};
int ans = 0;
while(now.fs>e||now.sc<e){
ans++;
auto nxt = getval(0,1,N,now.fs,now.sc);
if(nxt.fs == now.fs&&nxt.sc == now.sc)break;
now = nxt;
}
cout<<(now.fs>e||now.sc<e?-1:ans)<<'\n';
return;
}
int main(){
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>N>>K>>M;
for(int i = 0;i<M;i++){
int a,b;
cin>>a>>b;
if(a<=b){
int e = min(b+1,a+K);
rop[a].push_back(b);
rop[e].push_back(-b);
}
else{
int e = max(b-1,a-K);
lop[a].push_back(b);
lop[e].push_back(-b);
}
}
for(int i = 1;i<=N;i++)range[i].fs = range[i].sc = i;
multiset<int> st;
for(int i = 1;i<=N;i++){
for(auto &j:rop[i]){
if(j>0)st.insert(j);
else st.erase(st.find(-j));
}
if(!st.empty())range[i].sc = *st.rbegin();
}
st.clear();
for(int i = N;i>=1;i--){
for(auto &j:lop[i]){
if(j>0)st.insert(j);
else st.erase(st.find(-j));
}
if(!st.empty())range[i].fs = *st.begin();
}
build(0,1,N);
cin>>Q;
while(Q--)solve();
}
