#include <iostream>
#include <cassert>
#include <climits>
#include <bitset>
#include <stack>
#include <queue>
#include <iomanip>
#include <limits>
#include <string>
#include <cmath>
#include <set>
#include <map>
#include <math.h>
#include <algorithm>
#include <vector>
#include <string.h>
#include <tuple>

using namespace std;

typedef long long ll;
typedef pair<ll,ll> P;

long long int INF = 3e18;
double Pi = 3.1415926535897932384626;

vector<ll> G[500005];
vector<P> tree[500010];
priority_queue <ll> pql;
priority_queue <P> pqp;
//big priority queue
priority_queue <ll,vector<ll>,greater<ll> > pqls;
priority_queue <P,vector<P>,greater<P> > pqps;
//small priority queue
//top pop

int dx[8]={1,0,-1,0,1,1,-1,-1};
int dy[8]={0,1,0,-1,1,-1,-1,1};
char dir[] = "DRUL";
//ll bit[500005];
//↓,→,↑,←


#define p(x) cout<<x<<endl;
#define el cout<<endl;
#define pe(x) cout<<(x)<<" ";
#define ps(x) cout<<fixed<<setprecision(25)<<x<<endl;
#define pu(x) cout<<(x);
#define pd(x) cerr<<"//"<<(x)<<endl;
#define re(i,n) for(i=0;i<n;i++);
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define deba(x) cout<< #x << " = " << x <<endl


ll mod = 1000000007;
ll rui(ll number1,ll number2){
    if(number2 == 0){
        return 1;
    }else{
        ll number3 = rui(number1,number2 / 2);
        number3 *= number3;
        number3 %= mod;
        if(number2%2==1){
            number3 *= number1;
            number3 %= mod;
        }
        return number3;
    }
}
ll gcd(ll number1,ll number2){
    if(number1 > number2){
        swap(number1,number2);
    }
    if(number1 == 0 || number1 == number2){
        return number2;
    }else{
        return gcd(number2 % number1,number1);
    }
}
void YES(bool condition){
    if(condition){
        p("YES");
    }else{
        p("NO");
    }
    return;
}
void Yes(bool condition){
    if(condition){
        p("Yes");
    }else{
        p("No");
    }
    return;
}

ll n,m,num,sum,ans,a,b,c,d,e,f,g,h,i,j,k,w,ok,ng,l,q;
ll x[500005],y[500005],z[500005];
ll dp[3005][3005];
char s[500005],t[500005];
bool flag,dame;

int main(){
    cin >> n >> m >> k;
	for(i=0;i<m;i++){
		cin >> x[i] >> y[i];
	}
	for(i=1;i<=n;i++){
		dp[0][i] = 1;
	}
	for(i=1;i<=k;i++){
		for(j=0;j<m;j++){
			dp[i][y[j]] +=/* (y[j] - x[j] + 1) * */(dp[i-1][y[j]] - dp[i-1][x[j]-1] + mod);
			dp[i][x[j]-1] += /*(y[j] - x[j] + 1) * */(dp[i-1][x[j]-1] - dp[i-1][y[j]] + mod);
			dp[i][x[j]-1] += mod;
			dp[i][x[j]-1] %= mod;
		}
		for(j=n-1;j>=0;j--){
			dp[i][j] += dp[i][j+1];
			dp[i][j] %= mod;
		}
		for(j=1;j<=n;j++){
			dp[i][j] += dp[i][j-1];
			dp[i][j] %= mod;
		}
	}
	for(i=0;i<=k;i++){
		for(j=0;j<=n;j++){
			//pe(dp[i][j]);
		}
		//el;
	}
	ans = dp[k][n] - dp[k][n-1] + mod;
	ans %= mod;
	p(ans);
	return 0;
}