#include<bits/stdc++.h>
using namespace std;
#define loop(x,n) for(int x = 0; x < n; ++x)
#define ll long long int
int main()
{
    ll t;
    cin>>t;
    loop(z,t){
        ll n,m,k;
        cin>>n>>m>>k;
        if(n*m-1==k)
            cout<<"YES\n";
        else
            cout<<"NO\n";
    }
	return 0;
}