How do you add a property to a set of products? (2)

How do you add a property to a set of products? (2)
A . Create a sub type of the product item type and include the new required property
B . Create a new classification category and feature, and assign it to a catalog category
C . Create a new catalog version and include all products with the new required property
D . Create a new facet and include the new required property

Answer: B,C