#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> l_l;

#define EPS (1e-7)
#define INF (1e9)
#define PI (acos(-1))
const ll mod = 1000000007;
ll dp[3005][3005];
ll dpsum[3005][3005];
ll N, M, K;
ll L[3005], R[3005];

int main() {
    //cout.precision(10);
    cin.tie(0);
    ios::sync_with_stdio(false);
    cin >> N >> M >> K;
    for(int i = 1; i <= M; i++) cin >> L[i] >> R[i];
    dp[0][1] = 1;
    for(int i = 1; i <= N; i++) dpsum[0][i] = 1;
    for(int day = 1; day <= K; day++) {
        for(int m = 1; m <= M; m++) {
            ll before = (dpsum[day-1][R[m]] - dpsum[day-1][L[m]-1] % mod) % mod;
            dp[day][L[m]] += before;
            dp[day][R[m]+1] += mod - before;
            dp[day][L[m]] %= mod;
            dp[day][R[m]+1] %= mod;
        }
        for(int i = 1; i <= N; i++) dp[day][i] = (dp[day][i] + dp[day][i-1]) % mod;
        for(int i = 1; i <= N; i++) dpsum[day][i] = (dpsum[day][i-1] + dp[day][i]) % mod;
    }
    cout << dp[K][N] << endl;
    return 0;
}