// Hallelujah, praise the one who set me free
// Hallelujah, death has lost its grip on me
// You have broken every chain, There's salvation in your name
// Jesus Christ, my living hope
#include <bits/stdc++.h>
using namespace std;
#define REP(i, s, e) for (int i = (s); i < (e); i++)
#define RREP(i, s, e) for (int i = (s); i >= (e); i--)
template <class T>
inline bool mnto(T& a, T b) {return a > b ? a = b, 1 : 0;}
template <class T>
inline bool mxto(T& a, T b) {return a < b ? a = b, 1: 0;}
typedef long long ll;
typedef long double ld;
#define FI first
#define SE second
typedef pair<int, int> ii;
typedef pair<ll, ll> pll;
typedef tuple<int, int, int> iii;
#define ALL(_a) _a.begin(), _a.end()
#define SZ(_a) (int) _a.size()
#define pb push_back
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<ii> vii;
typedef vector<iii> viii;
#ifndef DEBUG
#define cerr if (0) cerr
#endif
const int INF = 1000000005;
const ll LINF = 1000000000000000005ll;
const int MAXN = 200005;
int n, k, m;
ii ab[MAXN];
int q;
int d[MAXN];
namespace dsu1 {
int par[MAXN], rnk[MAXN], rt[MAXN];
void init() {
REP (i, 1, n + 2) {
par[i] = i;
rnk[i] = 1;
rt[i] = i;
}
}
int findp(int i) {
if (par[i] == i) {
return i;
}
return par[i] = findp(par[i]);
}
bool join(int a, int b) {
int pa = findp(a), pb = findp(b);
if (pa == pb) {
return 0;
}
if (rnk[pa] < rnk[pb]) {
swap(pa, pb);
}
if (rnk[pa] == rnk[pb]) {
rnk[pa]++;
}
par[pb] = pa;
mxto(rt[pa], rt[pb]);
return 1;
}
}
namespace dsu2 {
int par[MAXN], rnk[MAXN], rt[MAXN];
void init() {
REP (i, 1, n + 2) {
par[i] = i;
rnk[i] = 1;
rt[i] = i;
}
}
int findp(int i) {
if (par[i] == i) {
return i;
}
return par[i] = findp(par[i]);
}
bool join(int a, int b) {
int pa = findp(a), pb = findp(b);
if (pa == pb) {
return 0;
}
if (rnk[pa] < rnk[pb]) {
swap(pa, pb);
}
if (rnk[pa] == rnk[pb]) {
rnk[pa]++;
}
par[pb] = pa;
mnto(rt[pa], rt[pb]);
return 1;
}
}
int main() {
#ifndef DEBUG
ios::sync_with_stdio(0), cin.tie(0);
#endif
cin >> n >> k >> m;
REP (i, 0, m) {
cin >> ab[i].FI >> ab[i].SE;
}
cin >> q;
while (q--) {
int s, t; cin >> s >> t;
REP (i, 1, n + 1) {
d[i] = INF;
}
d[t] = 0;
queue<int> qu;
qu.push(t);
dsu1::init();
while (!qu.empty()) {
int u = qu.front(); qu.pop();
REP (i, 0, m) {
auto [a, b] = ab[i];
if (a < b) {
if (u < a || u > b) {
continue;
}
while (dsu1::rt[dsu1::findp(a)] < min(a + k, b)) {
int j = dsu1::findp(a);
if (mnto(d[j], d[u] + 1)) {
qu.push(j);
}
dsu1::join(j, j + 1);
}
} else {
if (u < b || u > a) {
continue;
}
RREP (j, a, max(a - k, u) + 1) {
if (mnto(d[j], d[u] + 1)) {
qu.push(j);
}
}
}
}
}
if (d[s] == INF) {
cout << -1 << '\n';
} else {
cout << d[s] << '\n';
}
}
return 0;
}
