#include<bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define fi first
#define se second
const int N = 1e5+5;
const int lg = 17;
int n,k,m,q,mn[N][lg],mx[N][lg],l[N][lg],r[N][lg],idmx[N][lg],idmn[N][lg],lim[2];
vector<pii>a[2];
void build1(int id){
for(int i = 1; i <= lim[id]; i++) mn[i][0] = mx[i][0] = a[id][i-1].se;
for(int j = 1; j < lg; j++){
for(int i = 1; i+(1 << j)-1 <= lim[id]; i++){
mn[i][j] = min(mn[i][j-1],mn[i+(1 << (j-1))][j-1]);
mx[i][j] = max(mx[i][j-1],mx[i+(1 << (j-1))][j-1]);
}
}
}
int getidmx(int u, int v){
int k = __lg(v-u+1);
int x = idmx[u][k];
int y = idmx[v-(1 << k)+1][k];
if(r[x][0] <= r[y][0]) return y;
return x;
}
int getidmn(int u, int v){
int k = __lg(v-u+1);
int x = idmn[u][k];
int y = idmn[v-(1 << k)+1][k];
if(l[x][0] <= l[y][0]) return x;
return y;
}
void build2(){
for(int i = 1; i <= n; i++) idmx[i][0] = idmn[i][0] = i;
for(int j = 1; j < lg; j++){
for(int i = 1; i+(1 << j)-1 <= n; i++){
int x = idmx[i][j-1];
int y = idmx[i+(1 << (j-1))][j-1];
if(r[x][0] <= r[y][0]) idmx[i][j] = y;
else idmx[i][j] = x;
x = idmn[i][j-1];
y = idmn[i+(1 << (j-1))][j-1];
if(l[x][0] <= l[y][0]) idmn[i][j] = x;
else idmn[i][j] = y;
}
}
for(int j = 1; j < lg; j++){
for(int i = 1; i <= n; i++){
int x = l[i][j-1];
int y = r[i][j-1];
int loj1 = getidmn(x,y);
int loj2 = getidmx(x,y);
l[i][j] = min(l[loj1][j-1],l[loj2][j-1]);
r[i][j] = max(r[loj1][j-1],r[loj2][j-1]);
}
}
}
int getmin1(int l, int r){
int k = __lg(r-l+1);
return min(mn[l][k],mn[r-(1 << k)+1][k]);
}
int getmax1(int l, int r){
int k = __lg(r-l+1);
return max(mx[l][k],mx[r-(1 << k)+1][k]);
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> k >> m;
for(int i = 1; i <= m; i++){
int u,v;
cin >> u >> v;
if(u < v){
++lim[0];
a[0].push_back({u,v});
}
else{
++lim[1];
a[1].push_back({u,v});
}
}
sort(a[0].begin(),a[0].end());
build1(0);
for(int i = 1; i <= n; i++){
int ll = lower_bound(a[0].begin(),a[0].end(),make_pair(i-k+1,0))-a[0].begin()+1;
int rr = upper_bound(a[0].begin(),a[0].end(),make_pair(i+1,0))-a[0].begin();
if(ll > rr) r[i][0] = i;
else r[i][0] = max(i,getmax1(ll,rr));
}
sort(a[1].begin(),a[1].end());
build1(1);
for(int i = 1; i <= n; i++){
int ll = lower_bound(a[1].begin(),a[1].end(),make_pair(i,0))-a[1].begin()+1;
int rr = upper_bound(a[1].begin(),a[1].end(),make_pair(i+k,0))-a[1].begin();
if(ll > rr) l[i][0] = i;
else l[i][0] = min(i,getmin1(ll,rr));
}
build2();
cin >> q;
while(q--){
int s,t;
cin >> s >> t;
int ans = 0;
int ll = s;
int rr = s;
for(int i = lg-1; i >= 0; i--){
int loj1 = getidmn(ll,rr);
int loj2 = getidmx(ll,rr);
int x = min(l[loj1][i],l[loj2][i]);
int y = max(r[loj1][i],r[loj2][i]);
if(x <= t && y >= t) continue;
else{
ans += (1 << i);
ll = x;
rr = y;
}
}
int loj1 = getidmn(ll,rr);
int loj2 = getidmx(ll,rr);
int x = min(l[loj1][0],l[loj2][0]);
int y = max(r[loj1][0],r[loj2][0]);
if(x <= t && y >= t) cout << ans+1 << "\n";
else cout << -1 << "\n";
}
}
