Bonus points for anything that directly touches the real world (interfacing with hardware, automation, some parts of finance) and for stable fields (e.g. more like embedded C, less JavaScript).
1. Embedded systems are increasingly less subject to the constraints that require C.
2. Embedded systems are increasingly used for tasks where the difficulty in writing correct robust code in C produces life safety failures.
3. Gaining above average professionally applicable knowledge regarding embedded systems is likely to be more easily acquired in a short timeline than professionally applicable knowledge in C for reasons 1 and 2. Particularly for a self study course.
4. Building stuff that touches the real world is more a matter of embedded systems than choice of language. Building such systems is as easy as buying an Rpi or Arduino and some wire and some sensors.
