#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <set>
#define PI pair<int, int>
using namespace std;
struct SegmentTree
{
int n;
vector<PI> data;
void combine(int v)
{
data[v].first = min(data[v << 1].first, data[v << 1 | 1].first);
data[v].second = max(data[v << 1].second, data[v << 1 | 1].second);
}
SegmentTree(int n) : n(n), data(vector<PI>(n << 1, {INT32_MAX, INT32_MIN}))
{
}
void build(int l, vector<PI> &I)
{
for (int i = 1; i <= l; ++i) data[n + i] = I[i];
for (int v = n - 1; v; --v) combine(v);
}
PI query(int l, int r)
{
l += n;
r += n;
PI ans = {INT32_MAX, INT32_MIN};
while (l < r)
{
if (l & 1)
{
ans = {min(ans.first, data[l].first), max(ans.second, data[l].second)};
l++;
}
if (r & 1)
{
--r;
ans = {min(ans.first, data[r].first), max(ans.second, data[r].second)};
}
l >>= 1;
r >>= 1;
}
return ans;
}
};
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n, m, q, k;
cin >> n >> k >> m;
vector<PI> forward;
vector<PI> backward;
multiset<int> ends;
vector<PI> I(n + 1);
int a, b;
for (int i = 0; i < m; ++i)
{
cin >> a >> b;
if (a < b)
{
forward.emplace_back(a, b);
forward.emplace_back(min(a + k, b), -b);
}
else
{
backward.emplace_back(a, b);
backward.emplace_back(max(a - k, b), -b);
}
}
sort(forward.begin(), forward.end());
sort(backward.begin(), backward.end(), greater<>());
auto itr = forward.begin();
for (int i = 1; i <= n; ++i)
{
while (itr != forward.end() && itr->first == i)
{
if (itr->second > 0) ends.insert(itr->second);
else ends.erase(ends.find(-itr->second));
++itr;
}
if (!ends.empty()) I[i].second = *ends.rbegin();
else I[i].second = i;
}
itr = backward.begin();
for (int i = n; i; --i)
{
while (itr != backward.end() && itr->first == i)
{
if (itr->second > 0) ends.insert(itr->second);
else ends.erase(ends.find(-itr->second));
++itr;
}
if (!ends.empty()) I[i].first = *ends.rbegin();
else I[i].first = i;
}
vector<SegmentTree> interval(20, SegmentTree(1 << 17));
interval[0].build(n, I);
for (int j = 1; j < 20; ++j)
{
for (int i = 1; i <= n; ++i)
{
I[i] = interval[j - 1].query(I[i].first, I[i].second + 1);
}
interval[j].build(n, I);
}
cin >> q;
while (q--)
{
cin >> a >> b;
if (b < interval[19].query(a, a + 1).first || b > interval[19].query(a, a + 1).second) cout << "-1\n";
else
{
int res = 1;
int l = a;
int r = a;
for (int j = 19; j >= 0; -- j)
{
PI qry = interval[j].query(l, r + 1);
if (b < qry.first || b > qry.second)
{
res += 1 << j;
l = qry.first;
r = qry.second;
}
}
cout << res << "\n";
}
}
}
