#include<iostream>
#include<vector>
#include<algorithm>
#include<queue>
#include<stack>
#include<cstring>
#include<utility>
#include<cmath>
#include<assert.h>
#include<set>
#include<map>
#include<unordered_set>
#include<unordered_map>
#include<complex>

#define int long long
using namespace std;
#define rep(i, n) for(int i=0;i<(n);++i)
typedef pair<int, int> pii;
const int INF = 1l << 60;
#define u_b upper_bound
#define l_b lower_bound

int dp[3030][3030];
int N, M, K;
int L[3030], R[3030];
int s[3030];
int imos[3030];
const int mod = 1000000007;

signed main() {
    cin >> N >> M >> K;
    rep(i, M) {
        cin >> L[i] >> R[i];
        --L[i], --R[i];
    }
    dp[0][0] = 1;
    for (int i = 1; i <= N; ++i)s[i] = 1;
    rep(i, K) {
        rep(j, M) {
            int sum = s[R[j] + 1] - s[L[j]];
            imos[L[j]] += sum;
            imos[R[j] + 1] -= sum;
        }
        rep(j, N) {
            dp[i + 1][j] = (j ? dp[i + 1][j - 1] : 0) + imos[j];
            dp[i + 1][j] %= mod;
            s[j + 1] = s[j] + dp[i + 1][j];
            imos[j] = 0;
        }
    }
    cout << (dp[K][N - 1] % mod + mod) % mod << endl;
}