#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cassert>
#include <iostream>
#include <iomanip>
#include <string>
#include <stack>
#include <queue>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <bitset>

#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()
#define debug(x) cerr << #x << ": " << x << endl

using namespace std;

typedef long long ll;
typedef pair<ll, ll> Pll;
typedef pair<int, int> Pii;

const ll MOD = 1000000007;

int main() {
    int N,M,K;
    cin >> N >> M >> K;

    vector<Pii> elevators(M);
    for(int i=0;i<M;++i) {
        cin >> elevators[i].first >> elevators[i].second;
    }

    vector< vector<ll> > dp(K+1, vector<ll>(N+2, 0LL));
    dp[0][1] = 1LL;
    for(int i=0;i<K;++i) {
        for(int j=1;j<=N+1;++j) {
            dp[i][j] += dp[i][j-1];
            dp[i][j] %= MOD;
        }
    
        for(int j=0;j<M;++j) {
            if(!dp[i][elevators[j].first]) continue;
            ll total = (dp[i][elevators[j].second] - dp[i][elevators[j].first-1] + MOD) % MOD;
            dp[i+1][elevators[j].first] += total;
            dp[i+1][elevators[j].first] %= MOD;
            dp[i+1][elevators[j].second+1] += MOD - total;
            dp[i+1][elevators[j].second+1] %= MOD;
        }

        for(int j=1;j<=N+1;++j) {
            dp[i+1][j] += dp[i+1][j-1];
            dp[i+1][j] %= MOD;
        }
    }

    cout << dp[K][N] << endl;
}