#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {



    int n,m,k;
    cin>>n>>m>>k;
    if(((n-1)*1+(m-1)*n)==k){
        cout<<"YES"<<endl;
    }
    else
        cout<<"NO"<<endl;
    }
}
