#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;
vector<int> a;
int n;
void build(int n_, vector<int> &b) {
v.resize(__lg(n_) + 1, vector<int>(n_));
n = n_;
a = b;
for (int i = 0; i < n; i++) {
v[0][i] = a[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;
vector<int> a;
int n;
void build(int n_, vector<int> &b) {
v.resize(__lg(n_) + 1, vector<int>(n_));
n = n_;
a = b;
for (int i = 0; i < n; i++) {
v[0][i] = a[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);
map<pair<int, int>, int> used;
queue<pair<int, int>> bfs;
vector<int> g;
vector<pair<int, int>> segs;
for (int i = 0; i < n; i++) {
used[{i, i}] = (int)used.size();
bfs.emplace(i, i);
g.emplace_back();
segs.emplace_back(i, i);
}
while (!empty(bfs)) {
auto [l, r] = bfs.front();
bfs.pop();
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 (used.find({lf, rf}) == used.end()) {
used[{lf, rf}] = (int)used.size();
bfs.emplace(lf, rf);
g.emplace_back();
segs.emplace_back(lf, rf);
}
g[used[{l, r}]] = used[{lf, rf}];
}
vector<vector<int>> up(20, vector<int>(g.size()));
for (int i = 0; i < g.size(); i++) {
up[0][i] = g[i];
}
for (int i = 1; i < 20; i++) {
for (int v = 0; v < g.size(); v++) {
up[i][v] = up[i - 1][up[i - 1][v]];
}
}
int q; cin >> q;
while (q--) {
int s, t; cin >> s >> t;
s--, t--;
int cnt = 0, ans = INF;
int v = s;
for (int i = 19; i >= 0; i--) {
int vs = up[i][v];
if (segs[vs].first <= t && t <= segs[vs].second) continue;
v = vs;
cnt += (1 << i);
}
cnt++;
v = g[v];
if (segs[v].first <= t && t <= segs[v].second) {
ans = cnt;
}
if (ans == INF) cout << -1 << '\n';
else cout << ans << '\n';
}
}
