#include <bits/stdc++.h>
using namespace std;
long long fac[200010], finv[200010], inv[200010]; 
long long P = 1000000007;
void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < 200005; i++) {
        fac[i] = fac[i - 1] * i % P;
        inv[i] = P - inv[P % i] * (P / i) % P;
        finv[i] = finv[i - 1] * inv[i] % P;
    }
}
long long COM(int n, int k) {
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % P) % P;
}
int main(){
	int H, W, N; 
	cin >> H >> W >> N; 
	pair<int, int> A[3010]; 
	for(int i = 0; i < N; i++){
		cin >> A[i].first >> A[i].second; 
		A[i].first --; A[i].second--; 
	}
	A[N].first = H-1; A[N].second = W-1; 
	sort(A, A+N+1); 
	COMinit(); 
	long long dp[3010] = {}; // 初めてi番目の点でぶつかる場合の数
	for(int i = 0; i <= N; i++){
		dp[i] = COM(A[i].first + A[i].second, A[i].first); 
		for(int j = 0; j < i; j++){
			dp[i] += P - dp[j] * COM(A[i].first + A[i].second - A[j].first - A[j].second, A[i].first - A[j].first) % P; 
			dp[i] %= P; 
		}
	}
	cout << dp[N] << endl; 
}