I am the first.
C was the precursor to pretty much all of the most widely used programming languages today. Some like C++ and Objective-C are built on top of C and the C compiler, while others like Java are separate but use similar syntax.
I am in apple.
Apple's software is all built on C as far as I know (Swift and Objective-C are both built on top of C).
I am a language.
C is a programming language.
I am there in above lines, of course here also.
C is in things from the previous lines: Apple, programming languages, etc. and the letter C is also in this line, in the phrase "of course".
Beginners prefer me.
C is one of the first languages any new programmer should learn and is taught at some point in just about every Computer Science curriculum. It is up for debate whether beginners actually prefer C or are forced to learn it for their own good, but for a lot of programmers these days it reminds them of college classes when they were first learning data structures, operating systems, etc.