#include <iostream>
#include <iomanip>
#include <vector>
#include <set>
#include <string>
#include <queue>
#include <algorithm>
#include <map>
#include <cmath>
#include <numeric>
#include <list>
#include <stack>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <tuple>

using namespace std;

/*
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vpii;
*/

typedef long long ll;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef pair<long long, long long> pll;
typedef vector<pll> vpll;

typedef long double ld;
typedef vector<ld> vld;

typedef vector<bool> vb;

/*
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define reps(i, n) for (ll i = 1; i <= (n); i++)
#define rrep(i, n) for (ll i = (n) - 1; i >= 0; i--)
#define rreps(i, n) for (ll i = (n); i >= 1; i--)
#define all(v) (v).begin(), (v).end()
*/

template <class T> void chmin(T& a, T b) { a = min(a, b);}
template <class T> void chmax(T& a, T b) { a = max(a, b);}

constexpr int INF = 1 << 30;
constexpr ll INFL = 1LL << 60;
constexpr ll MOD = 1000000007;
constexpr ld EPS = 1e-9;

struct mint {
    ll x;
    mint(ll x=0):x((x%MOD+MOD)%MOD){}
    mint operator-() const { return mint(-x);}
    mint& operator+=(const mint a) {if ((x+=a.x)>=MOD) x-=MOD; return *this;}
    mint& operator-=(const mint a) {if ((x+=MOD-a.x)>=MOD) x-=MOD; return *this;}
    mint& operator*=(const mint a) {(x*=a.x)%=MOD; return *this;}
    mint operator+(const mint a) const {mint res(*this); return res+=a;}
    mint operator-(const mint a) const {mint res(*this); return res-=a;}
    mint operator*(const mint a) const {mint res(*this); return res*=a;}
    mint pow(ll t) const {
        if (!t) return 1;
        mint a = pow(t>>1);
        a *= a;
        if (t&1) a *= *this;
        return a;
    }

    // for prime mod
    mint inv() const { return pow(MOD-2);}
    mint& operator/=(const mint a) { return (*this) *= a.inv();}
    mint operator/(const mint a) const {mint res(*this); return res/=a;}
};

const int cmax = 200010;
mint fac[cmax],finv[cmax],inv[cmax];

void com_init() {
    fac[0]=fac[1]=1;
    finv[0]=finv[1]=1;
    inv[1]=1;
    for (int i=2; i<cmax; i++) {
        fac[i]=fac[i-1]*i;
        inv[i]=-inv[MOD%i]*(MOD/i);
        finv[i]=finv[i-1]*inv[i];
    }
}

ll com(int n, int k) {
    if (n<k) return 0;
    if (n<0||k<0) return 0;
	mint ret=fac[n]*finv[k]*finv[n-k];
    return ret.x;
}

void solve() {
    ll h, w, n;
    cin >> h >> w >> n;
    vpll p;
    for(ll i = 0; i < n; i++) {
        ll r, c;
        cin >> r >> c;
        p.push_back(make_pair(r, c));
    }
    p.push_back(make_pair(1, 1));
    p.push_back(make_pair(h, w));
    sort(p.begin(), p.end());

    com_init();
    vector<vector<mint>> dp(n + 2, vector<mint>(2));
    dp[0][1] = 1;
    for(ll i = 1; i <= n + 1; i++) {
        for(ll j = 0; j < i; j++) {
            ll dr = p[i].first - p[j].first;
            ll dc = p[i].second - p[j].second;
            if(dc < 0) continue;
            for(ll m = 0; m < 2; m++) {
                dp[i][1 - m] += dp[j][m] * com(dr + dc, dc);
            }
        }
    }
    mint ans = dp[n + 1][0] - dp[n + 1][1];
    cout << ans.x << endl;
    return;
}

int main() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(15);
    solve();
}


Measured memory_bytes: 5120