#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif
const int N = 1e5 + 5, LG = 17;
int n, k, m, q;
int lg[N], a[2 * N], b[2 * N];
array<int, 2> spt[LG][LG][N], A[N];
vector<int> add[N], del[N];
array<int, 2> operator + (const array<int, 2> &a, const array<int, 2> &b) {
return {min(a[0], b[0]), max(a[1], b[1])};
}
array<int, 2> qry(int k, int l, int r) {
int f = lg[r - l + 1];
return spt[k][f][l] + spt[k][f][r - (1 << f) + 1];
}
void init(array<int, 2> spt[LG][N]) {
for (int i = 1; i <= n; ++i) {
spt[0][i] = A[i];
}
for (int j = 1; j < LG; ++j) {
for (int i = 1; i + (1 << j) - 1 <= n; ++i) {
spt[j][i] = spt[j - 1][i] + spt[j - 1][i + (1 << j - 1)];
}
}
}
bool cov(const array<int, 2> &seg, int p) {
return seg[0] <= p && p <= seg[1];
}
int main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
cin >> n >> k >> m;
for (int i = 2; i <= n; ++i) {
lg[i] = lg[i / 2] + 1;
}
for (int i = 1; i <= m; ++i) {
cin >> a[i] >> b[i];
if (a[i] < b[i]) {
int r = min(a[i] + k - 1, b[i] - 1);
add[r].push_back(b[i]);
del[a[i]].push_back(b[i]);
}
}
multiset<int> st;
for (int i = n; i > 0; --i) {
for (int x : add[i]) {
st.insert(x);
}
A[i][1] = st.size() ? *st.rbegin() : i;
for (int x : del[i]) {
st.erase(st.find(x));
}
}
for (int i = 1; i <= n; ++i) {
add[i].clear();
del[i].clear();
}
for (int i = 1; i <= m; ++i) {
if (a[i] > b[i]) {
int l = max(a[i] - k + 1, b[i] + 1);
add[l].push_back(b[i]);
del[a[i]].push_back(b[i]);
}
}
for (int i = 1; i <= n; ++i) {
for (int x : add[i]) {
st.insert(x);
}
A[i][0] = st.size() ? *st.begin() : i;
for (int x : del[i]) {
st.erase(st.find(x));
}
}
init(spt[0]);
for (int j = 1; j < LG; ++j) {
for (int i = 1; i <= n; ++i) {
A[i] = qry(j - 1, A[i][0], A[i][1]);
}
init(spt[j]);
}
cin >> q;
while (q--) {
int s, t; cin >> s >> t;
array<int, 2> a{s, s};
int res = 0;
for (int j = LG - 1; ~j; --j) {
auto x = qry(j, a[0], a[1]);
if (!cov(x, t)) {
a = x;
res += 1 << j;
}
}
a = qry(0, a[0], a[1]);
cout << (cov(a, t) ? res + 1 : -1) << "\n";
}
return 0;
}
