Hi! I'm not from California but I think most nursing programs don't care if you've had to retake a prereq, they just factor in the highest grade of the two attempts. My program, for example, didn't have a place in the application process for specifying if any of the prereqs were taken more than once. Now, they did have a rule that only two attempts at a prereq were allowed, so they probably just pull transcripts to a) see if the class was taken more than twice, and b) make sure the applicant put the higher of the two grades on the application. Only the highest grade would factor into their decision.
Again, that's just my program, but I think most are structured similarly. I know loads of people who had to retake at least one prereq--some of them because they failed, and some because they needed a higher passing grade to be competitive.
Now, if your desired program includes GPA in their decision-making process, you might consider dropping and retaking before a failing grade could negatively impact it. Again, tons of people do this.
All in all, I would encourage you to do whatever will allow you to be competitive among applicants. Shoot for a stellar passing grade, not a barely-passing grade. Research their admission criteria carefully. If you ask program advisers, they'll usually tell you what the average grades, GPA, and test scores were of their previous cohort (I asked about this and the information was incredibly helpful).
