#include <bits/stdc++.h>
#include <unordered_set>
using namespace std;
#define ll long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define repeat(i,s,n) for(int (i)=s; (i)<(n); (i)++)
#define revrep(i,n) for(int (i)=(n)-1;i>=0; i--)

ll dp[3000+2][3000+2];
ll c[3000+1][3000+1];
const ll p=1e9+7;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout<<setprecision(std::numeric_limits<float>::max_digits10);
  int n,m,K;
  cin>>n>>m>>K;
  vector<int> l(m);
  vector<int> r(m);
  rep(i,m)cin>>l[i]>>r[i];
  repeat(x,1,n+1) {
    repeat(y,1,n+1) {
      ll tc=0;
      rep(i,m) {
        if(l[i]<=x&&x<=r[i]&&l[i]<=y&&y<=r[i])
          tc++;
      }
      c[x][y]=tc%p;
    }
  }
  memset(dp,0,sizeof(dp));
  dp[0][1]=1;
  // repeat(kk,1,k+1) {
  //   repeat(x,1,n+1) {
  //     repeat(y,1,n+1) {
  //       dp[kk][x]+=(dp[kk-1][y]*c[x][y])%p;
  //       dp[kk][x]%=p;
  //     }
  //   }
  // }
  repeat(k,1,K+1) {
    vector<ll> acc(n+1);
    repeat(x,1,n+1) {
      acc[x]+=acc[x-1]+dp[k-1][x];
      acc[x]%=p;
    }
    rep(i,m) {
      ll s=(acc[r[i]]-acc[l[i]-1]+p)%p;
      // imos
      dp[k][l[i]]+=s;
      dp[k][l[i]]%=p;
      dp[k][r[i]+1]+=(p-s);
      dp[k][r[i]+1]%=p;
    }
    repeat(x,1,n+2) {
      dp[k][x]+=dp[k][x-1];
      dp[k][x]%=p;
    }
  }
  cout << dp[K][n] << endl;
  return 0;
}