Exam Certified Data Architect topic 1 question 33 discussion

the question is pretty clear: What should a data architect recommend for MAINTAINING Sales Orders in Salesforce? -> so in order to maintain such big number of orders in salesforce you need Big Objects if the question was: What should a data architect recommend in order to view Sales Orders in Salesforce? -> external objects and Salesforce Connect (of course depending on the OData or some custom adapter)

B - doesn't need to live in SF, so external objects is best

B, since the data does not need to be stored or updated in salesforce, external objects are appropriate. https://trailhead.salesforce.com/content/learn/modules/big-data-strategy/compare-data-storage-options Not A. 150 million records should not go on a custom object. This would also require some sort of tool to frequently push and update data, which is unnecessary. Not C, because we do not need to store the data in salesforce. Not D. 150 million records should not be on a custom object. There is nothing more special about a standard object or custom object when it comes to data storage.