Answer :
C language is the the most basic language that is very native and generic in most of the other language in mobile , web or computer base applications. My suggestion is first you must consider the type of application you want to do if it is mobile you need to learn C then Java, Objective C, then android application is JSON. In other hand in web base application first is JavaScript, SQL and PHP, then JQUERY or ANGULAR JS. In computer base is either JAVA or C# or C++. If you are still sonfused the best option is start with JAVA