#include <iostream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <deque>
#include <queue>
#include <array>
#include <set>
#include <map>
#include <cmath>
#include <algorithm>
#include <numeric>
#include <cassert>
#include <utility>
#include <functional>

using namespace std;
using lli = long long int;
template<class T, class U> void init_n(vector<T>& v, size_t n, U x) 
{ v = vector<T>(n, x); }
template<class T> void init_n(vector<T>& v, size_t n) { init_n(v, n, T()); }
template<class T> void read_n(vector<T>& v, size_t n, size_t o = 0) 
{ v = vector<T>(n+o); for (lli i=o; i<n+o; ++i) cin >> v[i]; }
template<class T> void read_n(T a[], size_t n, size_t o = 0)
{ for (lli i=o; i<n+o; ++i) cin >> a[i]; }
template<class T> T gabs(const T& x) { return max(x, -x); }
#define abs gabs

const lli mod = 1e9+7;
lli n, m, k, dp[2][3002];
using P = pair<lli, lli>;
P ps[3001];
int main() {
  cin >> n >> m >> k;
  for (lli i=0; i<m; ++i) cin >> ps[i].first >> ps[i].second;
  for (lli i=1; i<=n; ++i) dp[0][i] = 1;
  for (lli i=1; i<=k; ++i) {
    for (lli j=1; j<=n; ++j) dp[i&1][j] = 0;
    for (lli l=0; l<m; ++l) {
      auto& p = ps[l];
      lli x = (mod + dp[(i^1)&1][p.second] - dp[(i^1)&1][p.first-1]) % mod;
      dp[i&1][p.first] = (dp[i&1][p.first] + x) % mod;
      dp[i&1][p.second+1] = (mod + dp[i&1][p.second+1] - x) % mod;
    }
    for (lli j=1; j<=n; ++j) { // imos
      dp[i&1][j] = (dp[i&1][j] + dp[i&1][j-1]) % mod;
    }
    for (lli j=1; j<=n; ++j) {
      dp[i&1][j] = (dp[i&1][j] + dp[i&1][j-1]) % mod;
    }
    /*
    for (lli i=1; i<=n; ++i) cerr << dp[i&1][i] << ' ';
    cerr << endl;
    */
  }
  cout << (mod + dp[k&1][n] - dp[k&1][n-1]) % mod << '\n';
  return 0;
}