First programming Language : C or Python?
The question is actually more complex than it might  appear, and really the answer can depend on the context. For example, at what age are the students when they are first taught to program? Is this in Primary School, High School or part of an undergraduate programme? The answer might be different in each case.
It also depends on the purpose of teaching the initial programming language (IPL). Is the purpose to lead towards a practical skill (vocational programming), or is it to enable the teaching of some knowledge of algorithms (pedagogic programming), is it to enable the functioning of some devices (engineering programming) or is it to prepare students for further study? Each of these questions could lead to a different language as an IPL.
For a very early age start of programming one does not have to worry about employment or future curricula so something engaging is important, so tools such as MIT Scratch have a role. For later childhood Python fills a nice niche, particularly as it can run on a wide variety of inexpensive  platforms (such as Arduino's, Raspberry Pi and so forth) which  provides accessibility and make it within the reach of the classroom and individual students.
Conversely, if one is looking at an undergraduate IPL then it may depend on which degree programme is being considered. Is it a degree in Computer Science, Engineering, Biology, Chemistry or Physics? One would then need to take into account what graduate employers might be looking for and tailor to that market.
Python might have value in some of these programs but the students would also have to learn other languages at some point. For example, Computer Scientists would need a wider experience that would embrace C#, C++ (among others). Electronic Engineers might need C, but Computer Scientists less so. Biologists might need R, Chemists and Physicists might still  need Fortran!
However, I would say that I might never recommend C as an IPL, and would start at C++ even for the most hardened Electrical Engineer. I only show Computer Science students C in specific contexts (like working with flex and bison)!
One thing I say to my students in the course where I look at Languages is that there is no one best language. The choice of language for any particular situation is so very context dependent on resources available, skills available, the purpose of the programming and the end goal of the task, and for an IPL that advice still holds true.