#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}

const int MAX_N = 3005;
ll bit[MAX_N];
int n; //　1-index
const ll MOD = 1e9+7;

void adds(int a, ll w){
    for(int x = a; x <= n; x += x & -x) bit[x] += w;
}
ll sums(int a){ 
    ll ret = 0;
    for(int x = a; x > 0; x -= x & -x) ret += bit[x];  
    return ret;
}

ll dp[MAX_N][MAX_N];

int main() {
    int m, k;
    cin >> n >> m >> k;
    int l[m], r[m];
    rep(i,m)cin >> l[i] >> r[i];

    dp[0][1] = 1;

    srep(i,1,k+1){
        rep(j,MAX_N)bit[j] = 0;
        ll sum[MAX_N] = {};
        srep(j,1,MAX_N){
            sum[j] = sum[j-1] + dp[i-1][j];
        }
        rep(j,m){
            ll wa = sum[r[j]] - sum[l[j] - 1];
            wa %= MOD;
            adds(l[j], wa);
            adds(r[j]+1, -wa);
        }
        srep(j,1,n+1){
            dp[i][j] = sums(j);
            dp[i][j] %= MOD;
        }
        /*
        srep(j,1,n+1){
            cout << sums(j) << ' ';
        }
        cout << endl;
        */
    }

    dp[k][n] %= MOD;
    cout << dp[k][n] << endl;
    return 0;
}