I am conducting a study and I am struggling finding an appropriate test for my hypothesis.

Here is the setting:

I have two independent measures. A is a categorical variable (e.g. gender) and B is an interval variable (e.g., SAT-score). My dependent variable C is ordinal.

First I expect to find that gender has an influence on C. Second I expect that B has an influence on C. And third I expect that the influence of A on C is stronger the higher B is.

Can someone help me find an appropriate test. I would be very grateful.

Thank you!