How far are you on math? PHY 9B requires you to have completed the equivalent of MAT 21C here. You should fulfill that if you’ve taken two semesters of calculus at a CC, but double check first. If you haven’t fulfilled that, as far as I’m aware you can’t enroll in PHY 9B. For PHY 9A you need the equivalent of MAT 21B, usually the first semester of calculus on a semester system (or passing the Calc BC exam).
I’d say to start with 9A to make sure you know everything you need to for the remaining physics classes. Definitely check with your orientation leader before you register to get advice about your specific situation.
Just so you know, for engineering you’re held to the requirements for when you’re graduating or the year before. So for example, anyone graduating in spring 2016 can choose to graduate under the 2014-2015 requirements or the 2015-2016 requirements for their major. All other colleges hold you to the requirements you came in under, 2015-2016 in your case, though you can choose to graduate under new requirements put in after you came in if you want. So while aunt bea’s advice holds for non-engineering majors, for engineering you need the most up to date requirements and the department websites and online catalog are more up to date than the physical catalog. The physical catalog is definitely helpful, but it’s outdated pretty much as soon as it’s printed so you can’t rely on it when your graduation requirements change every year or two.
Explanation of the graduation requirements for the college of engineering: http://catalog.ucdavis.edu/ugraded/engrreqt.html