Answer 1

Preference is preference, which is relative, so it's not even a matter of what you should prefer or not.

Honestly, you can pick ANY of them and that's a perfectly fine choice. There is no paved road that says you must complete x language in order to reach the destination where the other languages are.

Ask yourself what your short and long term goals are. I would base what I'm doing right now off of what I want to be doing later, and then create the means of making that exist later by doing what I need to right now. If you plan to focus on something that uses Java, then learn Java right now and focus there.