#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>

#include <iostream>
#include <complex>
#include <string>
#include <algorithm>
#include <numeric>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>

#include <functional>
#include <cassert>

typedef long long ll;
using namespace std;

#ifndef LOCAL
#define debug(x) ;
#else
#define debug(x) cerr << __LINE__ << " : " << #x << " = " << (x) << endl;

template <typename T1, typename T2>
ostream &operator<<(ostream &out, const pair<T1, T2> &p) {
  out << "{" << p.first << ", " << p.second << "}";
  return out;
}

template <typename T>
ostream &operator<<(ostream &out, const vector<T> &v) {
  out << '{';
  for (const T &item : v) out << item << ", ";
  out << "\b\b}";
  return out;
}
#endif

#define mod 1000000007 //1e9+7(prime number)
#define INF 1000000000 //1e9
#define LLINF 2000000000000000000LL //2e18
#define SIZE 3010

ll dp[SIZE][SIZE] = {};

int main(){
  int N, M, K;
  pair<int,int> ele[SIZE];

  cin >> N >> M >> K;

  for(int i=0;i<M;i++){
    int l, r;
    cin >> l >> r;
    ele[i] = {l, r};
  }

  sort(ele, ele + M);

  dp[0][1] = 1;
  dp[0][2] = -1;

  for(int i=0;i<K;i++){
    for(int j=0;j<N;j++) {
      dp[i][j+1] += dp[i][j];
      dp[i][j+1] %= mod;
    }

    for(int j=0;j<N;j++)
      dp[i][j+1] += dp[i][j];

    for(int j=0;j<M;j++){
      ll p = (dp[i][ele[j].second] - dp[i][ele[j].first-1]) % mod;
      dp[i+1][ele[j].first] += p;
      dp[i+1][ele[j].second+1] += mod - p;
    }
  }

  for(int j=0;j<N;j++)
    dp[K][j+1] += dp[K][j];

  cout << dp[K][N] % mod << endl;

  return 0;
}