Need to know the answers since confusing

General
1

QUESTION 2

With Pega’s Situational Layer CakeTM approach, how do you configure a regional variation for Human Resources (HR) time off cases?

  1. Create a rule for the variation and add the rule to the common layer of the application.
  2. Create a rule for the variation and add it to a secondary common application layer.
  3. Create a rule for the variation and add the rule to the layer for the region.
  4. Create a rule for the variation and replace the existing HR time off rule in the application common layer.

Answer: 3

I am confused with 2 and 3, can you tell me which one is the proper answer.