#include <bits/stdc++.h>
#include <random>

using namespace std;

typedef unsigned long long ull;
typedef long long ll;
typedef double ld;
#define int ll
typedef vector<char> vc;
typedef vector<vc> vvc;
typedef vector<vvc> vvvc;
typedef pair<int, int> pii;
typedef pair<pii, pii> piii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vpi;
typedef vector< vi > vvi;
typedef vector< vvi > vvvi;
typedef vector<short> vs;
typedef vector<vs> vvs;
typedef vector<vvs> vvvs;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef vector<ld> vld;
typedef vector<vld> vvld;
typedef vector<vvld> vvvld;
typedef vector<string> vst;
typedef vector<vst> vvst;
typedef pair<ld, ld> pld;

#define inmin(a, b) a = min(a, (b))
#define inmax(a, b) a = max(a, (b))
#define ALL(a) a.begin(),a.end()
#define RALL(a) a.rbegin(),a.rend()
#define sqr(x) ((x) * (x))
#define fori(i, n) for(int i = 0; i < int(n); ++i)
#define SZ(a) ((int)((a).size()))
#define triple(T) tuple<T, T, T>
#define quad(T) tuple<T, T, T, T>
#define watch(x) cerr << (#x) << " = " << (x) << endl;

#ifdef RUS_HOME
#define cerr cout
#else
#define cerr if (false) cerr
#endif

const double PI = 2 * acos(0.0);
#define rand shittttty_shit
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng_64(chrono::steady_clock::now().time_since_epoch().count());

const string DIGITS = "0123456789";
const string ALPH = "abcdefghijklmnopqrstuvwxyz";


template <class T0, class T1>
inline ostream & operator << (ostream &out, pair<T0, T1> &a) {
    return out << "{" << a.first << ", " << a.second << "}";
}

template <class T0, class T1>
inline istream & operator >> (istream &in, pair<T0, T1> &a) {
    return in >> a.first >> a.second;
}

template <class T0, class T1, class T2>
inline ostream & operator << (ostream &out, tuple<T0, T1, T2> &a) {
    return out << "{" << get<0>(a) << ", " << get<1>(a) << ", " << get<2>(a) << "}";
}

template <class T0, class T1, class T2, class T3>
inline ostream & operator << (ostream &out, tuple<T0, T1, T2, T3> &a) {
    return out << "{" << get<0>(a) << ", " << get<1>(a) << ", " << get<2>(a) << ", " <<  get<3>(a) << "}";
}

template<class T>
inline ostream & operator << (ostream &out, vector<T> &a) {
    out << "[";
    fori (i, a.size())
        out << a[i] << vector<string>{", ", "]  "}[i + 1 == a.size()];
    return out;
}


void smain();



signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
#ifdef RUS_HOME
    freopen("input", "r", stdin);
    clock_t start = clock();
#endif
    cout << setprecision(12) << fixed;
    smain();
#ifdef RUS_HOME
    cout << "\n\n\n\nTOTAL EXECUTION TIME: " << float( clock () - start ) /  CLOCKS_PER_SEC << endl;
#endif
    return 0;
}

const int MOD=1e9+7,N=2e5+100;
int fact[N],inv[N];

int binpow(int a,int n){
    int ans=1;
    while(n){
        if(n&1)
            ans=ans*a%MOD;
        a=a*a%MOD;
        n>>=1;
    }
    return ans;
}


void init(){
    fact[0]=1;
    for(int i=1;i<N;i++){
        fact[i]=fact[i-1]*i%MOD;
    }
    inv[N-1]=binpow(fact[N-1],MOD-2);
    for(int i=N-2;i>=0;i--){
        inv[i]=inv[i+1]*(i+1)%MOD;
    }
}

int ncr(int n, int k){
    if(k>n)
        return 0;
    return fact[n]*inv[k]%MOD*inv[n-k]%MOD;
}

int cnt(pii a, pii b){
    if(b.first<a.first||b.second<a.second)
        return 0;
    int n=b.first-a.first+1;
    int m=b.second-a.second+1;
    return ncr(n+m-2,n-1);
}

void smain() {
    init();
    int h,w,n;
    cin>>h>>w>>n;
    vpi kek(n);
    for(int i=0;i<n;i++){
        cin>>kek[i].first>>kek[i].second;
    }
    kek.push_back({h,w});
    sort(ALL(kek));
    vi lol(SZ(kek));
    for(int i=0;i<SZ(kek);i++){
        lol[i]=cnt({1,1},kek[i]);
    }

    for(int i=0;i<SZ(kek)-1;i++){
        for(int j=i+1;j<SZ(kek);j++){
            lol[j]=(lol[j]-lol[i]*cnt(kek[i],kek[j])%MOD+MOD)%MOD;
        }
    }

    cout<<lol.back();


}


Measured memory_bytes: 3456