#include<bits/stdc++.h>

using namespace std;

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

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);
    int test; cin >> test;
    while (test--) solve();
}