#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;
typedef long long ll;
ll n, m, k, l[3010], r[3010], dp[3010][3010];
const ll mod = 1000000007;

int main(void)
{
	cin >> n >> m >> k;
	for (ll i = 0; i < m; i++)
	{
		cin >> l[i] >> r[i];
	}
	for (ll i = 1; i <= n; i++)
	{
		dp[0][i] = 1;
	}
	for (ll i = 1; i <= k; i++)
	{
		for (ll j = 0; j < m; j++)
		{
			(dp[i][l[j]] += (mod + dp[i - 1][r[j]] - dp[i - 1][l[j] - 1])) %= mod;
			dp[i][r[j] + 1] += mod;
			(dp[i][r[j] + 1] -= (mod + dp[i - 1][r[j]] - dp[i - 1][l[j] - 1])) %= mod;
		}
		for (ll j = 1; j < n; j++)
		{
			(dp[i][j + 1] += dp[i][j]) %= mod;
		}
		for (ll j = 1; j < n; j++)
		{
			(dp[i][j + 1] += dp[i][j]) %= mod;
		}
	}
	cout << (mod + dp[k][n] - dp[k][n - 1]) % mod << endl;
}