#include <iostream>
#include <bits/stdc++.h>
int k,m,n;
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
int main(int argc, char** argv) {
	int t;
	scanf("%d",&t);
	for(int i=0;i<t;i++){
		scanf("%d %d %d",&n,&m,&k);
		if(n*m-1==k){
			printf("YES\n");
		}
		else{
			printf("NO\n");
		}
	}
	return 0;
}