I’d say that is highly subjective and the best person to make the choice is probably yourself.
That said, here’s my 2 cents.
If you care about doing a good job and getting a good grade, do the topic that interests you most and gives you the best chance at your end-goal (probably security theme from what you listed above).
Or maybe one that is closely related to the “specific” class (you haven’t mentioned what exactly the class is). For example if the class is about hardware, then maybe speaking about ARM/RiscV, their history and their ongoing hype/interest might be a nice idea.
If you need to present to the class and want engagement more than you want a grade, maybe you can do something tangentially relevant to your preferred topic but of more “general” interest.
Eg speak in regards to privacy (and touch on security), threat modelling, and offer relevant, extremely easily applicable options that anyone and everyone can make part of their everyday life (eg Librewolf/arkenfox, UblockOrigin, Tor Browser, VPNs, showcase easy steps to configure privacy in popular online services if available) to improve their QoL.
Or find some CVEs that are simple enough and easy to fall for, and present to everyone (set up an environment and replicate them live (if you look hard enough, I believe some CVEs are distributed with docker images or VMs for OFSEC practice reasons)) how easy it is for someone to exploit them. Eg this recent GNOME CVE would need just a download (not even opening the downloaded file).
If you care about engagement, I’d avoid things that most/many/some people might not even be able to grasp (eg, if 80% of your class is using Windows, they probably won’t even be able to understand (and won’t care to understand) how “portability” is relevant - if it is a .exe it works, right? 
).
Whatever you decide to do, make sure you enjoy it.
