Applying for job that requires bachelors degree, don't have one yet. What do I indicate for highest level of education completed?

Well, you got two different answers which gave you opposing advice. Your confusion is understandable. You don't want to ignore the instruction, which specifies "completed," and you have not actually completed your BA degree yet. But you are afraid to limit yourself to "high school," since that puts you at a disadvantage in comparison to the other candidates. Can you contact the personnel office and ask their preference? Take down the name of the person you speak with, and if anyone questions your action, you can always say, "I was advised by Ms. Snootwiggle to answer the question this way." You will have acted responsibly by trying to follow the rules, and if you are told to give yourself credit for a yet unfinished BA degree, it will not be the result of a lie on your part.

I would check the "High School" as your highest level of education completed. The purpose of submitting an online application and turning in a hard copy is for them to cross reference. If they like you enough to have you come in for an interview, you can always explain your situation once they ask. If the current potential job rejects your application just for that small education area, then there are plenty of other jobs you can apply for. Don't let one rejection destroy your hopes of applying for other places!

You could also state that the highest level completed was junior year of college with senior class graduation and B.S. pending.

Tick Bachelors as this will get you through. They can see on your resume what is happening.