The market has turned down hard as a result of a news-event, i.e., North Korea. That makes the decline tenuous, as it can just as easily reverse should tempers cool, even just a bit. Nonetheless, we trade the trend line, not the news. BABA reverses Short if below $172.32 at 1:30 PM (EDT). If so, we will be buying the Nov $165 puts, currently trading at about $6.00. As with FB, early entry is a judgment call based upon your own trading aggressiveness and discipline.