Which two options could meet this requirement?

Universal Containers (UC) has large data volumes and is nearing data storage limits. The planned solution is to archive historical data to reduce data storage in Salesforce; however, UC would still like to use reports, queries, and lookups on the archived information.

Which two options could meet this requirement? Choose 2 answers
A . Big objects
B . Custom objects
C . Related objects
D . External objects

Answer: A, D

Explanation:

Big objects and external objects can be used to archive historical data and reduce data storage in Salesforce, while still allowing users to access the archived data using reports, queries, and lookups. Big objects store data within Salesforce, while external objects store data outside Salesforce and integrate it with Salesforce using an external data source