#include <algorithm>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <iostream>
#include <map>
#include <memory>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
 
using namespace std;
 
typedef long long ll;
 
#define sz size()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(c) (c).begin(), (c).end()
#define rep(i,a,b) for(ll i=(a);i<(b);++i)
#define per(i,a,b) for(ll i=b-1LL;i>=(a);--i)
#define clr(a, b) memset((a), (b) ,sizeof(a))
#define ctos(c) string(1,c)
#define endl "\n"
#define print(x) cout<<#x<<" = "<<x<<endl;
 
#define MOD 1000000007

#define N_MAX 3010

struct bit{
  long long dat[N_MAX + 1];

  void init(){
    for(int i = 0; i < N_MAX; i++){
      dat[i] = 0;
    }
  }

  long long sum(int i){
  	if(i==0)return 0;
    long long s = 0;
    while(i > 0){
      s += dat[i];
      s %= MOD;
      i -= i & -i;
    }
    return s;
  }

  void add(int i, long long x){
    while(i <= N_MAX){
      dat[i] += x;
      dat[i] %= MOD;
      i += i & -i;
    }
  }
}bit1;

ll d[3010];

int main(){
	ll n,m,k;
	cin>>n>>m>>k;
	vector<pair<ll,ll> > vp;
	rep(i,0,m){
		ll a,b;
		cin>>a>>b;
		vp.pb(mp(a,b));
	}
	bit1.init();
	bit1.add(1,1);
	rep(K,0,k){
		clr(d,0);
		rep(i,0,vp.sz){
			ll l = vp[i].fi;
			ll r = vp[i].se;
			ll sum = (bit1.sum(r)+MOD)-bit1.sum(l-1);
			sum %= MOD;
			d[l] += sum;
			d[l] %= MOD;
			d[r+1] += MOD;
			d[r+1] -= sum;
			d[r+1] %= MOD;
		}
		rep(i,1,3005){
			d[i] += d[i-1];
			d[i] %= MOD;
		}
		bit1.init();
		rep(i,1,n+1){
			bit1.add(i,d[i]);
		}
	}
	cout << (bit1.sum(n)+MOD-bit1.sum(n-1))%MOD << endl;
	return 0;	
}