Please help me?

So i got my report card today but my parents don't know. They have to sign it and bring it back to school. I got mostly A's, one B and a C. I'm terrified of showing it to my parents. I think these are pretty good grades but they won't. They freak out whenever I get a B, I have no idea what they will do when they find out that I got a C. I studied really hard and I used to stay uo til 1 am studying. And my parents always think I'm slacking even though all i do is study. They never believe me when i tell them I'm studying, then they start yelling at me fkr procrastinating and slacking of. I admit that i do this stuff once in a while but it's very rare, besides I'm still 13. Anyway i know that i will eventually have to show it to them but how do i make them be ok with it?