#include <bits/stdc++.h>
using namespace std;
using ld = long double;
using ll = long long;
const int INF = 1e9, MOD = 1e9 + 7;
void solve();
signed main() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios::sync_with_stdio(false);
cin.tie(0);
int q = 1;
while (q--) {
solve();
}
}
struct sparse_table1 {
vector<vector<int>> v;
int n;
void build(int n_, vector<int> &b) {
v.resize(__lg(n_) + 1, vector<int>(n_));
n = n_;
for (int i = 0; i < n; i++) {
v[0][i] = b[i];
}
for (int j = 1; j <= __lg(n); j++) {
for (int i = 0; i + (1 << j) <= n; i++) {
v[j][i] = min(v[j - 1][i], v[j - 1][i + (1 << (j - 1))]);
}
}
}
int query(int l, int r) {
int j = __lg(r - l);
return min(v[j][l], v[j][r - (1 << j)]);
}
};
struct sparse_table2 {
vector<vector<int>> v;
int n;
void build(int n_, vector<int> &b) {
v.resize(__lg(n_) + 1, vector<int>(n_));
n = n_;
for (int i = 0; i < n; i++) {
v[0][i] = b[i];
}
for (int j = 1; j <= __lg(n); j++) {
for (int i = 0; i + (1 << j) <= n; i++) {
v[j][i] = max(v[j - 1][i], v[j - 1][i + (1 << (j - 1))]);
}
}
}
int query(int l, int r) {
int j = __lg(r - l);
return max(v[j][l], v[j][r - (1 << j)]);
}
};
sparse_table2 t1;
sparse_table1 t2;
void solve() {
int n, k; cin >> n >> k;
vector<int> e1(n, -1), e2(n, n);
int m; cin >> m;
for (int i = 0; i < m; i++) {
int a, b; cin >> a >> b;
a--, b--;
if (a <= b) {
e1[a] = max(e1[a], b);
} else {
e2[a] = min(e2[a], b);
}
}
t1.build(n, e1);
t2.build(n, e2);
vector<vector<int>> upl(19, vector<int>(n));
vector<vector<int>> upr(19, vector<int>(n));
vector<sparse_table1> s1(19);
vector<sparse_table2> s2(19);
for (int i = 0; i < n; i++) {
int l = i, r = i;
int lf = min(l, t2.query(l, min(n - 1, r + k - 1) + 1));
int rf = max(r, t1.query(max(0, l - k + 1), r + 1));
upl[0][i] = lf;
upr[0][i] = rf;
}
s1[0].build(n, upl[0]);
s2[0].build(n, upr[0]);
for (int i = 1; i < 19; i++) {
for (int v = 0; v < n; v++) {
int l = upl[i - 1][v];
int r = upr[i - 1][v];
int lf = l, rf = r;
lf = min(lf, s1[i - 1].query(l, r + 1));
rf = max(rf, s2[i - 1].query(l, r + 1));
upl[i][v] = lf;
upr[i][v] = rf;
}
s1[i].build(n, upl[i]);
s2[i].build(n, upr[i]);
}
int q; cin >> q;
while (q--) {
int s, t; cin >> s >> t;
s--, t--;
int cnt = 0, ans = INF;
int l = s, r = s;
for (int i = 18; i >= 0; i--) {
int lf = l, rf = r;
lf = min(lf, s1[i].query(l, r + 1));
rf = max(rf, s2[i].query(l, r + 1));
if (lf <= t && t <= rf) continue;
l = lf, r = rf;
cnt += (1 << i);
}
cnt++;
int lf = min(l, t2.query(l, min(n - 1, r + k - 1) + 1));
int rf = max(r, t1.query(max(0, l - k + 1), r + 1));
if (lf <= t && t <= rf) {
ans = cnt;
}
if (ans == INF) cout << -1 << '\n';
else cout << ans << '\n';
}
}
