#include <bits/stdc++.h>
using namespace std;
const int $L = 20;
int main() {
int N, K, M;
cin >> N >> K >> M;
array<vector<int>, $L> lb, rb;
lb.fill(vector<int>(2 * N, -1));
rb.fill(vector<int>(2 * N, -1));
vector<int> A(M), B(M);
for (int i = 0; i < M; i++) {
cin >> A[i] >> B[i];
A[i]--, B[i]--;
}
multiset<int> mse;
vector<vector<int>> ins(N), era(N);
for (int i = 0; i < M; i++) {
if (A[i] > B[i]) {
ins[A[i]].push_back(B[i]);
era[max(A[i] - K + 1, B[i] + 1)].push_back(B[i]);
}
}
for (int i = N - 1; i >= 0; i--) {
for (int k : ins[i])
mse.insert(k);
ins[i].clear();
lb[0][i + N] = min(i, mse.empty() ? N : *mse.begin());
for (int k : era[i])
mse.erase(mse.lower_bound(k));
era[i].clear();
}
assert(mse.empty());
for (int i = 0; i < M; i++) {
if (A[i] < B[i]) {
ins[A[i]].push_back(B[i]);
era[min(A[i] + K - 1, B[i] - 1)].push_back(B[i]);
}
}
for (int i = 0; i < N; i++) {
for (int k : ins[i])
mse.insert(k);
ins[i].clear();
rb[0][i + N] = max(i, mse.empty() ? 0 : *mse.rbegin());
for (int k : era[i])
mse.erase(mse.lower_bound(k));
era[i].clear();
}
assert(mse.empty());
for (int b = 1; b < $L; b++) {
for (int i = N - 1; i >= 1; i--) {
lb[b - 1][i] = min(lb[b - 1][i * 2], lb[b - 1][i * 2 + 1]);
rb[b - 1][i] = max(rb[b - 1][i * 2], rb[b - 1][i * 2 + 1]);
}
for (int i = 0; i < N; i++) {
int l = lb[b - 1][i + N], r = rb[b - 1][i + N];
int retl = N, retr = 0;
for (l += N, r += N + 1; l < r; l >>= 1, r >>= 1) {
if (l & 1) {
retl = min(retl, lb[b - 1][l]);
retr = max(retr, rb[b - 1][l]);
l++;
}
if (r & 1) {
r--;
retl = min(retl, lb[b - 1][r]);
retr = max(retr, rb[b - 1][r]);
}
}
lb[b][i + N] = retl, rb[b][i + N] = retr;
}
}
int Q;
cin >> Q;
while (Q--) {
int u, v;
cin >> u >> v;
u--, v--;
int l = u, r = u;
if (v < lb[$L - 1][u + N] || rb[$L - 1][u + N] < v) {
cout << -1 << '\n';
} else {
int ans = 0;
for (int b = $L - 1; b >= 0; b--) {
int retl = N, retr = 0;
for (int ll = l + N, rr = r + N + 1; ll < rr; ll >>= 1, rr >>= 1) {
if (ll & 1) {
retl = min(retl, lb[b][ll]);
retr = max(retr, rb[b][ll]);
ll++;
}
if (rr & 1) {
rr--;
retl = min(retl, lb[b][rr]);
retr = max(retr, rb[b][rr]);
}
}
if (v < retl || retr < v) {
l = retl, r = retr;
ans |= (1 << b);
}
}
cout << ans + 1 << '\n';
}
}
}
