#include<bits/stdc++.h>
using namespace std;

typedef long long int ll;

int main(){

    int t;
    cin>>t;

    while(t--){

       int n,m,k;
       cin>>n>>m>>k;

       int sol = n * m - 1;

       if(sol == k)cout<<"YES\n";
       else cout<<"NO\n";

    }    

    return 0;

}