#include <bits/stdc++.h>
using namespace std;
struct station {
int nxt, best;
bool operator<(const station &x) const {
return best < x.best;
}
};
struct train {
int a, b;
};
struct leftTrain {
int a, b;
bool operator<(const leftTrain &x) const {
if (b == x.b)
return a > x.a;
return b > x.b;
}
leftTrain(const train &t) {
a = t.a;
b = t.b;
}
};
struct rightTrain {
int a, b;
bool operator<(const rightTrain &x) const {
if (b == x.b)
return a > x.a;
return b < x.b;
}
rightTrain(const train &t) {
a = t.a;
b = t.b;
}
};
const int MAX_N = 1e5;
const int MAX_LOG_N = 16;
const int MAX_M = 2e5;
train trains[MAX_M];
priority_queue<leftTrain> bestLeftTrains;
priority_queue<rightTrain> bestRightTrains;
vector<train> leftTrainsByTime[MAX_N + 1], rightTrainsByTime[MAX_N + 1];
int minLeft[MAX_LOG_N + 1][MAX_N + 1], maxRight[MAX_LOG_N + 1][MAX_N + 1];
int queryMin(int p, int l, int r) {
int minn = MAX_N;
for (int i = l; i <= r; i++)
minn = min(minn, minLeft[p][i]);
return minn;
}
int queryMax(int p, int l, int r) {
int maxx = 0;
for (int i = l; i <= r; i++)
maxx = max(maxx, maxRight[p][i]);
return maxx;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, k, m;
cin >> n >> k >> m;
for (int i = 0; i < m; i++) {
cin >> trains[i].a >> trains[i].b;
if (trains[i].a < trains[i].b)
rightTrainsByTime[min(n, trains[i].a + k - 1)].push_back(trains[i]);
else
leftTrainsByTime[max(1, trains[i].a - k + 1)].push_back(trains[i]);
}
for (int i = 1; i <= n; i++) {
for (leftTrain t: leftTrainsByTime[i])
bestLeftTrains.push(t);
while (!bestLeftTrains.empty() && bestLeftTrains.top().a < i)
bestLeftTrains.pop();
minLeft[0][i] = i;
if (!bestLeftTrains.empty())
minLeft[0][i] = bestLeftTrains.top().b;
}
for (int i = n; i >= 1; i--) {
for (rightTrain t: rightTrainsByTime[i])
bestRightTrains.push(t);
while (!bestRightTrains.empty() && bestRightTrains.top().a > i)
bestRightTrains.pop();
maxRight[0][i] = i;
if (!bestRightTrains.empty())
maxRight[0][i] = bestRightTrains.top().b;
}
/* for (int i = 1; i <= n; i++) { */
/* printf("%d %d %d\n", i, minLeft[0][i], maxRight[0][i]); */
/* } */
for (int p = 1; p <= MAX_LOG_N; p++) {
for (int i = 1; i <= n; i++) {
int l = minLeft[p - 1][i], r = maxRight[p - 1][i];
minLeft[p][i] = queryMin(p - 1, l, r);
maxRight[p][i] = queryMax(p - 1, l, r);
}
}
int q;
cin >> q;
for (int i = 0; i < q; i++) {
int a, b;
cin >> a >> b;
int l = a, r = a;
int ans = 0;
for (int p = MAX_LOG_N; p >= 0; p--) {
int newL = queryMin(p, l, r);
int newR = queryMax(p, l, r);
if (newL <= b && b <= newR)
continue;
l = newL;
r = newR;
ans += (1 << p);
}
int newL = queryMin(0, l, r);
int newR = queryMax(0, l, r);
l = newL, r = newR;
ans++;
if (newL <= b && b <= newR)
cout << ans << "\n";
else
cout << "-1\n";
}
return 0;
}
