#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double ld;
typedef unsigned long long ull;
#define len(v) (int)((v).size())
const int LGN = 17;
const int N = 1 << LGN;
pair<int, int> tree[LGN][N << 1];
pair<int, int> merge(pair<int, int> &a, pair<int, int> &b){
return {min(a.first, b.first), max(a.second, b.second)};
}
void build(int k, int v, int l, int r, vector<pair<int, int>> &a){
if (r - l == 1){
tree[k][v] = a[l];
return;
}
int m = (l + r) / 2;
build(k, v * 2, l, m, a);
build(k, v * 2 + 1, m, r, a);
tree[k][v] = merge(tree[k][v * 2], tree[k][v * 2 + 1]);
}
const int inf = 1e9;
pair<int, int> sum(int k, int v, int l, int r, int ql, int qr){
if (l >= qr || ql >= r) return {inf, -inf};
if (l >= ql && r <= qr) return tree[k][v];
int m = (l + r) / 2;
pair<int, int> r1 = sum(k, v * 2, l, m, ql, qr);
pair<int, int> r2 = sum(k, v * 2 + 1, m, r, ql, qr);
return merge(r1, r2);
}
struct event{
int i, tp;
event(int i, int tp) : i(i), tp(tp){}
};
void solve() {
int n, k, m;
cin >> n >> k >> m;
vector<event> evs;
for (int i = 0; i < m; ++i){
int x, y;
cin >> x >> y;
--x, --y;
if (x < y){
evs.emplace_back(x, y + 1);
evs.emplace_back(min(x + k - 1, y), -y - 1);
}
else{
evs.emplace_back(max(y, x - k + 1), y + 1);
evs.emplace_back(x, -y - 1);
}
}
vector<pair<int, int>> a(n);
for (int i = 0; i < n; ++i){
evs.emplace_back(i, 0);
a[i] = {i, i};
}
sort(evs.begin(), evs.end(), [&](event x, event y){
if (x.i != y.i) return x.i < y.i;
return x.tp > y.tp;
});
multiset<int> s;
for (event ev : evs){
if (ev.tp == 0){
if (!s.empty()){
a[ev.i].first = min(a[ev.i].first, *s.begin());
a[ev.i].second = max(a[ev.i].second, *(--s.end()));
}
}
else if (ev.tp > 0){
s.insert(ev.tp - 1);
}
else{
s.erase(s.find(-(ev.tp + 1)));
}
}
int q;
cin >> q;
build(0, 1, 0, n, a);
for (int j = 1; j < LGN; ++j){
for (int i = 0; i < n; ++i){
a[i] = sum(j - 1, 1, 0, n, a[i].first, a[i].second + 1);
}
build(j, 1, 0, n, a);
}
for (int i = 0; i < q; ++i){
int x, y;
cin >> x >> y;
--x, --y;
if (x == y) {
cout << "0\n";
continue;
}
int ans = 0;
pair<int, int> cr = {x, x};
for (int j = LGN - 1; j >= 0; --j){
pair<int, int> nw = sum(j, 1, 0, n, cr.first, cr.second + 1);
if (nw.first <= y && y <= nw.second){
continue;
}
ans += (1 << j);
cr = nw;
}
cr = sum(0, 1, 0, n, cr.first, cr.second + 1);
if (cr.first <= y && y <= cr.second){
cout << ans + 1 << '\n';
}
else{
cout << "-1\n";
}
}
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
cout.precision(60);
int t = 1;
// cin >> t;
while (t--) {
solve();
}
}
