#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,a,b) for (int i = a; i <= b; ++i)
#define per(i,a,b) for (int i = a; i >= b; --i)
#define pii pair<int,int>
#define fi first
#define se second
#define all(v) (v).begin(), (v).end()
#define pb push_back
const int MAXN = 1e5 + 10;
vector<pii> g[2];
int p[MAXN][31][2];
int32_t main() {
ios_base::sync_with_stdio(0); cin.tie(nullptr);
int n,m,k,q; cin >> n >> k >> m;
rep(i,1,m) {
int u,v;cin >> u >> v;
g[(u>=v)].pb({u,v});
}
cin >> q;
sort(all(g[0]));
int ptr=0, mx = -1;
rep(i,1,n) {
while (ptr < g[0].size() && g[0][ptr].fi == i) {
mx = max(mx, g[0][ptr++].se);
}
p[i][0][0] = (mx<i?i:mx);
}
sort(all(g[1]), greater<pii>());
ptr = 0;
int mn = n;
per(i,n,1) {
while (ptr < g[1].size() && g[1][ptr].fi == i) {
mn = min(mn, g[1][ptr++].se);
}
p[i][0][1] = (mn>i?i:mn);
}
rep(k,0,1) {
rep(j,1,30) {
rep(i,1,n) {
p[i][j][k] = p[p[i][j-1][k]][j-1][k];
}
}
}
while (q--) {
int s,t;cin >> s >> t;
int ans = 0, ptr = s;
if (s <= t) {
per(k,30,0) {
if(p[ptr][k][0] < t) {
ptr = p[ptr][k][0];
ans+=(1<<k);
}
}
ptr = p[ptr][0][0];
cout << (ptr>=t ? ans+1 : -1) << '\n';
} else {
per(k,30,0) {
if(p[ptr][k][1] > t) {
ptr = p[ptr][k][1];
ans+=(1<<k);
}
}
ptr = p[ptr][0][1];
cout << (ptr<=t ? ans+1 : -1) << '\n';
}
}
}
