#include "bits/stdc++.h"
using namespace std;
#ifdef duc_debug
#include "bits/debug.h"
#else
#define debug(...)
#endif
const int maxn = 1e5 + 5;
const int LG = 17;
const int M = 2e5 + 5;
int n, k, m;
pair<int, int> operator + (const pair<int, int> &a, const pair<int, int> &b) {
return make_pair(min(a.first, b.first), max(a.second, b.second));
}
pair<int, int> inf = make_pair(1e9, 0);
struct segment_tree {
int n;
vector<pair<int, int>> tree;
vector<pair<int, int>> lazy;
segment_tree() {}
segment_tree(int n) : n(n), tree(n * 4 + 6, inf), lazy(n * 4 + 6, inf) {}
void down(int ind, int l, int r) {
tree[ind] = tree[ind] + lazy[ind];
if (l != r) {
lazy[ind << 1] = lazy[ind << 1] + lazy[ind];
lazy[ind << 1 | 1] = lazy[ind << 1 | 1] + lazy[ind];
}
lazy[ind] = inf;
}
void update(int x, int y, pair<int, int> val, int ind, int l, int r) {
if (lazy[ind] != inf) down(ind, l, r);
if (l > y || r < x) return;
if (x <= l and r <= y) {
lazy[ind] = val;
down(ind, l, r);
return;
}
int mid = (l + r) >> 1;
update(x, y, val, ind << 1, l, mid);
update(x, y, val, ind << 1 | 1, mid + 1, r);
tree[ind] = tree[ind << 1] + tree[ind << 1 | 1];
}
pair<int, int> get(int x, int y, int ind, int l, int r) {
if (lazy[ind] != inf) down(ind, l, r);
if (l > y || r < x) return make_pair(1e9, 0);
if (x <= l and r <= y) {
return tree[ind];
}
int mid = (l + r) >> 1;
return get(x, y, ind << 1, l, mid) + get(x, y, ind << 1 | 1, mid + 1, r);
}
void update(int x, int y, pair<int, int> val) { update(x, y, val, 1, 1, n); }
pair<int, int> get(int x, int y) { return get(x, y, 1, 1, n); }
} st[LG + 1], sx;
void solve() {
cin >> n >> k >> m;
sx = segment_tree(n);
for (int j = 0; j <= LG; ++j) {
st[j] = segment_tree(n);
}
for (int i = 1; i <= n; ++i) {
sx.update(i, i, make_pair(i, i));
}
for (int i = 1; i <= m; ++i) {
int a, b; cin >> a >> b;
if (a < b) {
sx.update(a, min(b, a + k - 1), make_pair(b, b));
} else {
sx.update(max(b, a - k + 1), a, make_pair(b, b));
}
}
for (int i = 1; i <= n; ++i) {
pair<int, int> x = sx.get(i, i);
st[0].update(i, i, x);
}
for (int j = 1; j <= LG; ++j) {
for (int i = 1; i <= n; ++i) {
pair<int, int> x = st[j - 1].get(i, i);
st[j].update(i, i, st[j - 1].get(x.first, x.second));
}
}
int q; cin >> q;
while (q--) {
int l, r; cin >> l >> r;
int res = 0;
pair<int, int> rg = make_pair(l, l);
auto its = [&](pair<int, int> a, int x) {
return a.first <= x and x <= a.second;
};
for (int i = LG; i >= 0; --i) {
pair<int, int> tr = st[i].get(rg.first, rg.second);
if (!its(tr, r)) {
res |= (1 << i);
rg = tr;
}
}
rg = st[0].get(rg.first, rg.second);
cout << (its(rg, r) ? res + 1 : -1) << '\n';
}
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
solve();
return 0;
}
