#include <iostream>

using namespace std;
long long dp[3002][3002] = {},sum[3002][3002] = {},l[3010],r[3010],mod = 1000000007;
int main(){
	int i,j,n,m,k;
	cin >> n >> m >> k;
	for(i=0;i<m;i++){
		cin >> l[i] >> r[i];
	}
	dp[0][1] = 1;
	for(i=1;i<=n;i++) sum[0][i] = 1;
	for(i=1;i<=k;i++){
		for(j=0;j<m;j++){
			(dp[i][l[j]] += (sum[i-1][r[j]] - sum[i-1][l[j]-1] + mod)%mod) %= mod;
			dp[i][r[j]+1] -= (sum[i-1][r[j]] - sum[i-1][l[j]-1] + mod)%mod;
			(dp[i][r[j]+1] += mod) %= mod;
		}
		sum[i][1] = dp[i][1];
		for(j=2;j<=n;j++){
			(dp[i][j] += dp[i][j-1]) %= mod;
			sum[i][j] = (sum[i][j-1] + dp[i][j])%mod;
		}
	}
	cout << dp[k][n] << endl;
}