#include <bits/stdc++.h>
#define seg pair <int, int>
#define l first
#define r second
using namespace std;
const int N = 1e5 + 5;
const int lg = 18;
int n, k, m, q;
seg s[N], rmq[lg][N];
struct segtree{
seg it[4 * N], lazy[4 * N];
seg mer(seg a, seg b){
return seg(min(a.l, b.l), max(a.r, b.r));
}
void build(seg *a, int s = 1, int l = 1, int r = n){
lazy[s] = {n + 1, 0};
if (l == r){
it[s] = a[l];
return;
}
int mid = l + r >> 1;
build(a, 2 * s, l, mid);
build(a, 2 * s + 1, mid + 1, r);
it[s] = mer(it[2 * s], it[2 * s + 1]);
}
void update(int u, int v, seg val, int s = 1, int l = 1, int r = n){
if (u <= l && r <= v){
lazy[s] = mer(lazy[s], val);
return;
}
int mid = l + r >> 1;
if (mid >= u) update(u, v, val, 2 * s, l, mid);
if (mid + 1 <= v) update(u, v, val, 2 * s + 1, mid + 1, r);
}
void getpoint(int u, seg &ans, int s = 1, int l = 1, int r = n){
ans = mer(ans, lazy[s]);
if (l == r){
ans = mer(ans, it[s]);
return;
}
int mid = l + r >> 1;
if (mid >= u) getpoint(u, ans, 2 * s, l, mid);
else getpoint(u, ans, 2 * s + 1, mid + 1, r);
}
void getseg(seg p, seg &ans, int s = 1, int l = 1, int r = n){
if (p.l <= l && r <= p.r){
ans = mer(ans, it[s]);
return;
}
int mid = l + r >> 1;
if (mid >= p.l) getseg(p, ans, 2 * s, l, mid);
if (mid + 1 <= p.r) getseg(p, ans, 2 * s + 1, mid + 1, r);
}
} tree, tr[lg];
bool check(seg p, int t){
return p.l <= t && t <= p.r;
}
void solve(){
cin >> n >> k >> m;
for (int i = 1; i <= n; ++ i) s[i] = {i, i};
tree.build(s);
for (int i = 1, a, b; i <= m; ++ i){
cin >> a >> b;
if (a < b) tree.update(a, min(a + k - 1, b - 1), seg(n + 1, b));
else tree.update(max(a - k + 1, b + 1), a, seg(b, 0));
}
for (int i = 1; i <= n; ++ i) rmq[0][i] = {n + 1, 0}, tree.getpoint(i, rmq[0][i]);
tr[0].build(rmq[0]);
for (int l = 1; l < lg; ++ l){
for (int i = 1; i <= n; ++ i) rmq[l][i] = {n + 1, 0}, tr[l - 1].getseg(rmq[l - 1][i], rmq[l][i]);
tr[l].build(rmq[l]);
}
cin >> q;
while (q --){
int s, t; cin >> s >> t;
if (s == t){
cout << 0 << '\n';
return;
}
if (!check(rmq[lg - 1][s], t)){
cout << -1 << '\n';
continue;
}
int ans = 0;
seg cur = {s, s};
for (int l = lg - 2; l >= 0; -- l){
seg ck = {n + 1, 0};
tr[l].getseg(cur, ck);
if (!check(ck, t)){
ans += (1 << l);
cur = ck;
}
}
cout << ans + 1 << '\n';
}
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
solve();
return 0;
}
