I am going to assume that you are either in the USA or in Canada. If this is wrong let us know.
In the US, and in Canada, medical school is a graduate program. First you get your bachelor’s degree, then you apply to medical schools.
At one point in the distant past one daughter considered medical school as an option. I asked two different doctors I know where the other students in their MD program had gotten their bachelor’s degree. One said “all over the place”. The other said essentially the same thing.
I do not have any MD’s in my immediate family. I do have three close relatives who got or are currently getting some sort of medical related graduate degree (two master’s degrees, one DVM, and a PhD in progress). All of them have said essentially the same thing. The other students in their medical-related graduate program came from a very, very wide range of undergraduate universities. All of these were by the way in highly ranked graduate programs.
You do not need to attend a “top 20” university for your bachelor’s degree to get accepted to very good MD or DO programs (or very good master’s, DVM, or PhD programs). You do not need to attend a “top 100” university for a bachelor’s in order to get accepted to very good MD or DO programs (or …).
By the way, your daughter’s 3.86 unweighted GPA is very close to my older daughter’s high school unweighted GPA. She is at work today. At work they call her “doctor” (she is the one with a DVM). This GPA will help to get your daughter into universities that are very good for premed students.
Both daughters had undergraduate majors that overlapped a lot with premed classes, and both knew quite a few premed students from these classes. The required premed classes are tough at any “top 200” university. These classes will be full of very strong students. I am not a big fan of jumping ahead in these classes. Students really do get stronger as they go through their education. Waiting to take the toughest classes, or perhaps pacing oneself carefully in taking these classes, is a good plan.
But I would not worry about one B+ somewhere along the way. There will be lots more B’s for most students who end up being called “doctor”.
This might actually be advice that is worth thinking about. You can major in nearly anything, complete the premed required classes, and apply to medical schools. There is for example at least one video on-line by someone who majored in art, completed the premed requirements, went to medical school, and became a surgeon specializing in robot-assisted surgery. In the video he paints a very small picture of the hospital where he works, using the robot-assisted surgery system to do the painting.
One reason that many premed students major in biology is that the required courses overlap a lot with the required premed classes. Another reason is probably that they find it interesting and are good at it. However, there are a lot of premed students who major in biology, and most premed students do not actually end up in medical school. Having some “plan B” in mind is a good idea.
And to me it sounds like your daughter is doing very well.