The effects of one bad grade?

On my mid year grades I will have a C+ in AP calculus BC, with the rest As. I am posting to ask whether or not this make a big difference in getting admitted to my top choice schools? One of my top choices, Notre Dame, does not require mid year grades, but should I still send these in because I got As in the rest of my classes? Thank you in advance for replying.

Are you applying for STEM?

I think a C+ will have a slight negative effect on your application, especially since its in AP Calculus BC (a core class). Do you have any circumstances that can explain this low grade?

For any truly optional mid-year report schools, do not send yours.

Don’t send the C to Notre Dame if it is not required.

Anymore opinions?