Without knowing anything about your students, it's hard to say. If I were the student I'd much prefer to be taught C, but that's because I have an existing interest in computers and a desire to develop systems programming skills. I wouldn't like to teach JS to anyone because it's a bad language and I don't want students to go away making more web 3 slop but if they actively are interested in making web 3 slop that'd be a case for teaching JS. I'm of the pedagogical school of teaching students what they are actually interested in learning. They might not know enough about programming to know which language they want to learn off the bat, but maybe ask them what sort of software they're interested in making. If they want to make websites, you might want to teach them something like Python with Flask, as something less bad than JS as well as easy enough to learn.

Imo C is a good teaching language as it teaches you a lot about how computers work, as well as the fact that nearly everything runs on C. It is "harder" though, and imo is also for students who are actually interested.