#include <bits/stdc++.h>
#define fst first
#define snd second
#define pb push_back
#define SZ(x) (int)x.size()
#define ALL(x) x.begin(),x.end()
#define forn(i,a,b) for(int i = a; i<b; i++)
#define mset(a,v) memset(a,v,sizeof(a))
#define FIN ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
using namespace std;
typedef long long ll;
const int MAXN = 200000+5;
const int MAXP = 20;
#ifdef D
#define debug(x) cout << x
#else
#define debug(x) //nothing
#endif
struct STreeMin{
ll n;
vector<ll> st;
STreeMin(ll n=0):n(n), st(4*n+5,1000000000){}
void upd(ll k, ll l, ll r, ll p, ll v){
if(l+1==r){ st[k]=v; return; }
ll mid = (l+r)/2;
if(mid>p) upd(2*k,l,mid,p,v);
else upd(2*k+1,mid,r,p,v);
st[k]=min(st[2*k],st[2*k+1]);
}
ll query(ll k, ll l, ll r, ll L, ll R){
if(l>=R || r<=L) return 1000000000;
if(l>=L && r<=R) return st[k];
ll mid = (l+r)/2;
return min(query(2*k,l,mid,L,R),query(2*k+1,mid,r,L,R));
}
void upd(ll p, ll v){ upd(1,0,n,p,v); }
ll query(ll l, ll r){ return query(1,0,n,l,r); }
};
struct STreeMax{
ll n;
vector<ll> st;
STreeMax(ll n=0):n(n), st(4*n+5,(ll)0){}
void upd(ll k, ll l, ll r, ll p, ll v){
if(l+1==r){ st[k]=v; return; }
ll mid = (l+r)/2;
if(mid>p) upd(2*k,l,mid,p,v);
else upd(2*k+1,mid,r,p,v);
st[k]=max(st[2*k],st[2*k+1]);
}
ll query(ll k, ll l, ll r, ll L, ll R){
if(l>=R || r<=L) return (ll)0;
if(l>=L && r<=R) return st[k];
ll mid = (l+r)/2;
return max(query(2*k,l,mid,L,R),query(2*k+1,mid,r,L,R));
}
void upd(ll p, ll v){ upd(1,0,n,p,v); }
ll query(ll l, ll r){ return query(1,0,n,l,r); }
};
ll n,K;
ll m,q;
ll a[MAXN];
ll b[MAXN];
ll s[MAXN];
ll t[MAXN];
STreeMin lleft[MAXP];
STreeMax rright[MAXP];
void precalc(){
forn(i,0,MAXP) rright[i]=STreeMax(n), lleft[i]=STreeMin(n);
forn(k,0,MAXP){
forn(i,0,n) lleft[k].upd(i,i), rright[k].upd(i,i);
}
set<pair<ll,ll>> inp;
multiset<ll> disp;
set<pair<ll,ll>> out;
forn(i,0,m){
if(a[i]<b[i]) inp.insert({a[i],b[i]});
}
forn(i,0,n){
while(!inp.empty() && inp.begin()->fst<=i){
disp.insert(inp.begin()->snd);
out.insert({inp.begin()->fst+K, inp.begin()->snd});
inp.erase(inp.begin());
}
rright[0].upd(i,i);
if(!disp.empty()) rright[0].upd(i,*(--disp.end()));
while(!out.empty() && out.begin()->fst<=i){
disp.erase(disp.find(out.begin()->snd));
out.erase(out.begin());
}
}
inp.clear();
disp.clear();
out.clear();
forn(i,0,m){
if(a[i]>b[i]) inp.insert({a[i]*-1,b[i]*-1});
}
for(int i = n-1; i>=0; i--){
debug("i: "<<i<<'\n');
while(!inp.empty() && inp.begin()->fst*-1>=i){
disp.insert(inp.begin()->snd*-1);
debug("Ingreso "<<inp.begin()->fst*-1<<" "<<inp.begin()->snd*-1<<'\n');
out.insert({(inp.begin()->fst*-1 - K)*-1 ,inp.begin()->snd});
inp.erase(inp.begin());
}
lleft[0].upd(i,i);
if(!disp.empty()) lleft[0].upd(i,*disp.begin());
while(!out.empty() && out.begin()->fst*-1>=i){
disp.erase(disp.find(out.begin()->snd*-1));
debug("Sale "<<out.begin()->fst*-1+K<<" "<<out.begin()->snd*-1<<'\n');
out.erase(out.begin());
}
}
forn(k,1,MAXP){
forn(i,0,n){
debug("(Left) Para "<<i<<" "<<"paso "<<k<<" "<<"tomamos desde "<<lleft[k-1].query(i,i+1)<<" hasta "<< rright[k-1].query(i,i+1)+1<<'\n');
rright[k].upd(i, rright[k-1].query(lleft[k-1].query(i,i+1), rright[k-1].query(i,i+1)+1));
lleft[k].upd(i, lleft[k-1].query(lleft[k-1].query(i,i+1), rright[k-1].query(i,i+1)+1));
}
}
forn(i,0,n){
debug("Desde i (Right): "<<i<<'\n');
forn(k,0,MAXP){
debug("( Paso "<<(1<<k)<<" ) "<<rright[k].query(i,i+1)<<"\n");
} debug('\n');
debug("Desde i (Left): "<<i<<'\n');
forn(k,0,MAXP){
debug("( Paso "<<(1<<k)<<" ) "<<lleft[k].query(i,i+1)<<"\n");
} debug('\n');
}
}
int main(){
cin>>n>>K; K--;
cin>>m;
forn(i,0,m) cin>>a[i]>>b[i], a[i]--, b[i]--;
cin>>q;
forn(i,0,q) cin>>s[i]>>t[i], s[i]--, t[i]--;
precalc();
forn(i,0,q){
ll p = s[i];
ll l = s[i];
ll r = s[i];
ll cnt = 0;
for(int k = MAXP-1; k>=0; k--){
ll nl = lleft[k].query(l,r+1);
ll nr = rright[k].query(l,r+1);
if(nl<=t[i] && t[i]<=nr) continue;
l=nl;
r=nr;
cnt+=1<<k;
}
debug(l<<" "<<r<<" - "<<cnt<<'\n');
ll nl = lleft[0].query(l,r+1);
ll nr = rright[0].query(l,r+1);
if(nl<=t[i] && t[i]<=nr) cout<<cnt+1<<'\n';
else cout<<-1<<'\n';
}
return 0;
}
