fix typo: option 3

Author: jakevdp

docs/jep/12049-type-annotations.md

@@ -292,7 +292,7 @@ This may be purer from an OOP perspective, but it reintroduces a bifurcation and
 
 ##### Evaluation
 
-There is no perfect option here, but weighing the pros and cons of these solutions, I (@jakevdp) believe that Option 4 presents the best path forward.
+There is no perfect option here, but weighing the pros and cons of these solutions, I (@jakevdp) believe that Option 3 presents the best path forward.
 It offers the least confusing API for users (`jax.Array` is the only object you need to worry about), and does not require any significant restructuring of our existing codepaths.
 There is one minor technical hurdle involved; that is that `jax.Array` will be defined in C++ via pybind11, and pybind11 currently [does not support](https://github.com/pybind/pybind11/issues/2696) custom metaclasses required for overriding `__instancecheck__`; nevertheless we should be able to work around this.