#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
struct node {
int l, r, mn, mx;
node *left, *right;
};
node *build(int l, int r, const vector<int> &_mn, const vector<int> &_mx) {
if (l == r) return new node{l, r, _mn[l], _mx[l], nullptr, nullptr};
node *left = build(l, (l + r) / 2, _mn, _mx), *right = build((l + r) / 2 + 1, r, _mn, _mx);
return new node{l, r, min(left->mn, right->mn), max(left->mx, right->mx), left, right};
}
pair<int, int> query(node *cur, int l, int r) {
if (cur->l > r || cur->r < l) return {INF, -INF};
if (l <= cur->l && cur->r <= r) return {cur->mn, cur->mx};
auto left = query(cur->left, l, r), right = query(cur->right, l, r);
return {min(left.first, right.first), max(left.second, right.second)};
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, k, max_log;
cin >> n >> k;
max_log = ceil(log2(n)) + 1;
int m;
cin >> m;
vector< vector<int> > mx_diff(n + 1), mn_diff(n + 1);
while (m--) {
int a, b;
cin >> a >> b;
if (a < b) {
mx_diff[a].push_back(b);
if (min(a + k, b + 1) <= n) mx_diff[min(a + k, b + 1)].push_back(-b);
} else {
mn_diff[a].push_back(b);
if (max(a - k, b - 1) >= 1) mn_diff[max(a - k, b - 1)].push_back(-b);
}
}
vector<int> mn(n + 1), mx(n + 1);
iota(mn.begin(), mn.end(), 0);
iota(mx.begin(), mx.end(), 0);
map<int, int> mp;
for (int i = 1; i <= n; i++) {
for (auto &x : mx_diff[i]) {
if (x > 0) mp[x]++;
else if (--mp[-x] == 0) mp.erase(-x);
}
if (!mp.empty()) mx[i] = mp.rbegin()->first;
}
mp.clear();
for (int i = n; i >= 1; i--) {
for (auto &x : mn_diff[i]) {
if (x > 0) mp[x]++;
else if (--mp[-x] == 0) mp.erase(-x);
}
if (!mp.empty()) mn[i] = mp.begin()->first;
}
vector<node*> up(max_log + 1);
up[0] = build(1, n, mn, mx);
for (int i = 1; i <= max_log; i++) {
for (int j = 1; j <= n; j++) {
tie(mn[j], mx[j]) = query(up[i - 1], mn[j], mx[j]);
}
up[i] = build(1, n, mn, mx);
}
int q;
cin >> q;
while (q--) {
int s, t;
cin >> s >> t;
int l, r;
tie(l, r) = query(up[max_log], s, s);
if (t < l || t > r) {
cout << -1 << '\n';
continue;
}
l = s, r = s;
int ans = 0;
for (int i = max_log; i >= 0; i--) {
int nl, nr;
tie(nl, nr) = query(up[i], l, r);
if (t < nl || t > nr) {
l = nl, r = nr;
ans += (1 << i);
}
}
cout << ans + 1 << '\n';
}
return 0;
}
