
Explanation:
Box 1: External
Consumption Pricing Tier of API Management does not support Built-in Cache. Therefore caching-type should be set to "external".
Box 2: private
We need to ensure that the data is not available to other customers, we need to use the cache type of Private caching.
Box 3: Authorization
The calls are being authenticated by OAuth, the caching can vary by the Authorization header.
Reference:
https://docs.microsoft.com/en-us/azure/api-management/api-management-caching-policies