Both. And it's a sliding scale in real life - you might be completely Kanban, or completely Scrum, or somewhere between, where you're doing some Scrum ceremonies and processes but skipping the ones that don't help you .
I usually look at the processes the team want to do, and the main question is "how do you want to plan your work?"
If you want to be planning, estimating and agreeing fixed amounts of work to be delivered in specific time periods, Scrum. If you simply want to let things flow in ad-hoc and let your leads prioritise and the developers take things off a to-do list whenever they're ready, Kanban. Most people do something in-between.
If you try one and it doesn't work, it does not matter. You can swap to the other. Better, you can do both at the same time. There are plenty of places I know of that are doing Scrum pretty much full on. And while they're running Scrum "properly", they're using Kanban boards to visualise, focus and supplement their Scrum process.