#include<bits/stdc++.h>
using ll = long long;
const int N = 1e5, LOG = 18;
int n;
struct segtree {
int mx[2 * N], mn[2 * N];
void build() {
std::copy(mn, mn + n, mn + n);
std::copy(mx, mx + n, mx + n);
for (int i = n - 1; i > 0; --i) {
mx[i] = std::max(mx[i << 1], mx[i << 1 | 1]);
mn[i] = std::min(mn[i << 1], mn[i << 1 | 1]);
}
}
std::pair<int, int> get(int l, int r) {
int tl = n, tr = -1;
for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
if (l & 1) {
tl = std::min(tl, mn[l]);
tr = std::max(tr, mx[l]);
++l;
}
if (~r & 1) {
tl = std::min(tl, mn[r]);
tr = std::max(tr, mx[r]);
--r;
}
}
return {tl, tr};
}
} tr[LOG];
signed main() {
std::cin.tie(nullptr)->sync_with_stdio(false);
int k, m;
std::cin >> n >> k >> m;
std::vector<std::vector<std::pair<int, int>>> occl(n), occr(n);
for (int i = 0; i < m; ++i) {
int a, b;
std::cin >> a >> b;
--a, --b;
if (a < b) {
occl[a].emplace_back(b, 1);
occl[std::min(b, a + k)].emplace_back(b, -1);
} else {
occr[a].emplace_back(b, 1);
occr[std::max(b, a - k)].emplace_back(b, -1);
}
}
std::vector<int> lft(n), rgt(n);
std::multiset<int> st;
for (int i = 0; i < n; ++i) {
for (auto [x, t] : occl[i]) {
if (t == 1) st.insert(x);
else st.extract(x);
}
if (st.empty()) rgt[i] = i;
else rgt[i] = *--st.end();
}
for (int i = n - 1; i >= 0; --i) {
for (auto [x, t] : occr[i]) {
if (t == 1) st.insert(x);
else st.extract(x);
}
if (st.empty()) lft[i] = i;
else lft[i] = *st.begin();
}
for (int i = 0; i < n; ++i) {
std::tie(tr[0].mn[i], tr[0].mx[i]) = {lft[i], rgt[i]};
}
tr[0].build();
for (int j = 0; j + 1 < LOG; ++j) {
for (int i = 0; i < n; ++i) {
auto [l, r] = tr[j].get(i, i);
std::tie(tr[j + 1].mn[i], tr[j + 1].mx[i]) = tr[j].get(l, r);
}
tr[j + 1].build();
}
int q;
std::cin >> q;
while (q--) {
int s, t;
std::cin >> s >> t;
--s, --t;
if (s == t) {
std::cout << "0\n";
continue;
}
auto [fl, fr] = tr[LOG - 1].get(s, s);
if (t < fl || fr < t) {
std::cout << "-1\n";
continue;
}
int l = s, r = s, ans = 0;
for (int j = LOG - 1; j >= 0; --j) {
auto [nl, nr] = tr[j].get(l, r);
if (nr < t || t < nl) {
ans += 1 << j;
l = nl, r = nr;
}
}
std::cout << ans + 1 << '\n';
}
}
