And once we deactivate this, it cannot combine with factor B, and so it cannot follow this alternative pathway. Now, another protein is factor H. And factor H actually removes the BB protein from this complex, once again, deactivating this pathway. And finally, we also have another important agent that plays a role in the classical pathway, and that is the C one inhibitor. So remember, the C one is that initial protein that needs to be activated by the antibody antigen complex in the classical pathway. And what this C one inhibitor does is it goes on to bind to that C one complex in the classical pathway and inhibits the activation of C two. And and so that cannot form the C four B, c, two a C, two B complex.