This covers content or UI designed to alarm users into a hasty action — false claims of malware infection, urgent "your device is at risk" messaging — used to drive installs, purchases, or permission grants through fear rather than genuine need.
A frequent pattern is an ad creative (sometimes from a third-party ad network, not the app itself) claiming the user's phone is infected, which links through to install another app.
"Your app or an ad served within it makes false claims about the security or performance of the user's device to induce a download or purchase, per the Social Engineering policy."