#include<cstdio>
#include<cstring>
#include<vector>
#include<queue>
#include<stack>
#include<algorithm>
#include<cmath>
#include<climits>
#include<string>
#include<set>
#include<numeric>
#include<map>
#include<iostream>
using namespace std;
#define rep(i,n) for(int i = 0;i<((int)(n));i++)
#define reg(i,a,b) for(int i = ((int)(a));i<=((int)(b));i++)
#define irep(i,n) for(int i = ((int)(n)-1);i>=0;i--)
#define ireg(i,a,b) for(int i = ((int)(b));i>=((int)(a));i--)
typedef long long ll;
typedef pair<ll, ll> mp;
//LLONG_MIN

/*

*/

ll dp[3010]={},ru[3010],n,m,k,l[3010],r[3010],mod=1e9+7;

int main(void){
	cin>>n>>m>>k;
	rep(i,m){
		cin>>l[i]>>r[i];
	}
	dp[1]=1;
	// cout<<-1<<endl;
	// rep(i,n+1)cout<<dp[i]<<" ";
	// cout<<endl;
	rep(i,k){
		ru[0]=0;
		reg(j,1,n)ru[j]=(ru[j-1]+dp[j]) % mod;
		reg(j,1,n)dp[j]=0;
		rep(j,m){
			dp[l[j]]=(dp[l[j]] +ru[r[j]]-ru[l[j]-1]+mod) % mod;
			dp[r[j]+1]=(dp[r[j]+1] -ru[r[j]]+ru[l[j]-1]+mod) % mod;
		}
		reg(j,1,n){
			dp[j]=(dp[j]+dp[j-1]) % mod;
		}
		// cout<<i<<endl;
		// rep(i,n+1)cout<<dp[i]<<" ";
		// cout<<endl;
		// rep(i,n+1)cout<<ru[i]<<" ";
		// cout<<endl;
	}
	cout<<dp[n]<<endl;
	return 0;
}