#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using vc = vector<char>;
using vvc = vector<vc>;
using pll = pair<ll, ll>;
using vpll = vector<pll>;
const ll INF = 1LL << 60;
const ll MOD = 1e9 + 7;
#define rep(i, n) for (ll i = 0; i < (n); i++)
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}
#ifndef ONLINE_JUDGE
    #define debug(x) cerr << #x << ": " << x << endl;
#else
    #define debug(x)
#endif

// modint: mod 計算を int を扱うように扱える構造体
template<int MOD> struct Fp {
    long long val;
    constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
        if (val < 0) val += MOD;
    }
    constexpr int getmod() { return MOD; }
    constexpr Fp operator - () const noexcept {
        return val ? MOD - val : 0;
    }
    constexpr Fp operator + (const Fp& r) const noexcept { return Fp(*this) += r; }
    constexpr Fp operator - (const Fp& r) const noexcept { return Fp(*this) -= r; }
    constexpr Fp operator * (const Fp& r) const noexcept { return Fp(*this) *= r; }
    constexpr Fp operator / (const Fp& r) const noexcept { return Fp(*this) /= r; }
    constexpr Fp& operator += (const Fp& r) noexcept {
        val += r.val;
        if (val >= MOD) val -= MOD;
        return *this;
    }
    constexpr Fp& operator -= (const Fp& r) noexcept {
        val -= r.val;
        if (val < 0) val += MOD;
        return *this;
    }
    constexpr Fp& operator *= (const Fp& r) noexcept {
        val = val * r.val % MOD;
        return *this;
    }
    constexpr Fp& operator /= (const Fp& r) noexcept {
        long long a = r.val, b = MOD, u = 1, v = 0;
        while (b) {
            long long t = a / b;
            a -= t * b; swap(a, b);
            u -= t * v; swap(u, v);
        }
        val = val * u % MOD;
        if (val < 0) val += MOD;
        return *this;
    }
    constexpr bool operator == (const Fp& r) const noexcept {
        return this->val == r.val;
    }
    constexpr bool operator != (const Fp& r) const noexcept {
        return this->val != r.val;
    }
    friend constexpr ostream& operator << (ostream &os, const Fp<MOD>& x) noexcept {
        return os << x.val;
    }
    friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
        if (n == 0) return 1;
        auto t = modpow(a, n / 2);
        t = t * t;
        if (n & 1) t = t * a;
        return t;
    }
};

// 二項係数ライブラリ
template<class T> struct BiCoef {
    vector<T> fact_, inv_, finv_;
    constexpr BiCoef() {}
    constexpr BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) {
        init(n);
    }
    constexpr void init(int n) noexcept {
        fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1);
        int MOD = fact_[0].getmod();
        for(int i = 2; i < n; i++){
            fact_[i] = fact_[i-1] * i;
            inv_[i] = -inv_[MOD%i] * (MOD/i);
            finv_[i] = finv_[i-1] * inv_[i];
        }
    }
    constexpr T com(int n, int k) const noexcept {
        if (n < k || n < 0 || k < 0) return 0;
        return fact_[n] * finv_[k] * finv_[n-k];
    }
    constexpr T fact(int n) const noexcept {
        if (n < 0) return 0;
        return fact_[n];
    }
    constexpr T inv(int n) const noexcept {
        if (n < 0) return 0;
        return inv_[n];
    }
    constexpr T finv(int n) const noexcept {
        if (n < 0) return 0;
        return finv_[n];
    }
};

using mint = Fp<MOD>;
BiCoef<mint> bc;

// dp[i][j] 壁iまでみて、偶奇がjの場合の数
mint dp[3100][2];

mint route(pll p1, pll p2) {
    ll x1 = p1.first, y1 = p1.second;
    ll x2 = p2.first, y2 = p2.second;
    if(x1 > x2 || y1 > y2) return 0;
    return bc.com(x2-x1+y2-y1, x2-x1);
}

int main() {
    cin.tie(0);ios::sync_with_stdio(false);cout << fixed << setprecision(20);

    bc.init(210000);
    ll H, W, N;
    cin >> H >> W >> N;
    vpll vp;
    vp.emplace_back(1, 1);
    rep(i, N) {
        ll r, c;
        cin >> r >> c;
        vp.emplace_back(r, c);
    }

    sort(vp.begin(), vp.end());
    dp[0][0] = 1;
    for(ll i = 1; i <= N; i++) {
        for(ll j = 0; j < i; j++) {
            dp[i][0] += dp[j][1] * route(vp[j], vp[i]);
            dp[i][1] += dp[j][0] * route(vp[j], vp[i]);
        }
    }
    mint ng = 0;
    for(ll i = 1; i <= N; i++) {
        ng += dp[i][1] * route(vp[i], pll(H, W));
        ng -= dp[i][0] * route(vp[i], pll(H, W));
    }

    mint ans = bc.com(H+W-2, H-1) - ng;
    cout << ans << endl;
}


Measured memory_bytes: 5376