#include "bits/stdc++.h"
using namespace std;
#define int long long
#define double long double
const int MAXN = 2e5 + 10;
const int MOD = 1e9 + 7;
mt19937_64 rng((int)std::chrono::steady_clock::now().time_since_epoch().count());
int rnd(int x, int y) {
int u = uniform_int_distribution<int>(x, y)(rng); return u;
}
int bm(int b, int p) {
if(p==0) return 1 % MOD;
int r = bm(b, p >> 1);
if(p&1) return (((r*r) % MOD) * b) % MOD;
return (r*r) % MOD;
}
int inv(int b) {
return bm(b, MOD-2);
}
int fastlog(int x) {
return (x == 0 ? -1 : 64 - __builtin_clzll(x) - 1);
}
void printcase(int i) { cout << "Case #" << i << ": "; }
static void run_with_stack_size(void (*func)(void), size_t stsize) {
char *stack, *send;
stack = (char *)malloc(stsize);
send = stack + stsize - 16;
send = (char *)((uintptr_t)send / 16 * 16);
asm volatile(
"mov %%rsp, (%0)\n"
"mov %0, %%rsp\n"
:
: "r"(send));
func();
asm volatile("mov (%0), %%rsp\n" : : "r"(send));
free(stack);
}
void solve(int tc) {
int n, k, m;
cin >> n >> k >> m;
int dist[n+1][n+1];
for(int i=1; i<=n; i++) {
for(int j=1; j<=n; j++) {
dist[i][j] = (i == j ? 0 : 1e9);
}
}
for(int i=1; i<=m; i++) {
int a, b;
cin >> a >> b;
if(a < b) {
for(int j=a; j<a+k; j++) {
for(int l=j+1; l<=b; l++) {
dist[j][l] = 1;
}
}
}
else {
for(int j=a; j>a-k; j--) {
for(int l=j-1; l>=b; l--) {
dist[j][l] = 1;
}
}
}
}
for(int l=1; l<=n; l++) {
for(int i=1; i<=n; i++) {
for(int j=1; j<=n; j++) {
dist[i][j] = min(dist[i][j], dist[i][l]+dist[l][j]);
}
}
}
int q;
cin >> q;
while(q--) {
int s, t;
cin >> s >> t;
cout << (dist[s][t] >= 1e7 ? -1 : dist[s][t]) << '\n';
}
}
void uwu() {
ios::sync_with_stdio(0); cin.tie(0);
int t = 1; //cin >> t;
for(int i=1; i<=t; i++) solve(i);
}
int32_t main() {
#ifdef ONLINE_JUDGE
uwu();
#endif
#ifndef ONLINE_JUDGE
run_with_stack_size(uwu, 1024 * 1024 * 1024); // run with a 1 GiB stack
#endif
}
/*
g++ brute.cpp -std=c++17 -O2 -o brute
./brute < input.txt
*/
