Correct Answers: A and B
Reason:-
Reference data is a fixed data set that is static or, in some cases, changes slowly. Here the metadata values of sensors are slowly changing and thus can be considered as reference data as the question tells. Azure blob storage can ingest this type of data, in which the data is modeled to be a sequence of blobs in ascending order of the date/time specified in the blob name. Similarly, Azure SQL also can intake reference data. In this case, the data is retrieved by Job in stream analytics and is stored with snapshot memory for further processing.
Options A and B correct: Azure SQL and Blob storage are supported input services for reference data.
Options C and D incorrect: Azure Event Hub and IoT hub are not supported.
