What could cause a discrepancy in sales data between the Finance team and the Inventory team using Cloud Pub/Sub?

The selection regarding the discrepancy in sales data due to the Inventory team's subscriber only receiving messages that are published after the subscription was created is valid because of how Cloud Pub/Sub manages message delivery. When a subscription to a topic is created, it begins receiving messages from that moment forward. Any messages published before the subscription was created will not be sent to that subscriber, which can lead to missing critical sales data that the Finance team may have accounted for.

For instance, if there were sales logged before the Inventory team's subscription was established, those specific sales data points would never reach the Inventory team's processing system. This could ultimately result in a mismatch or discrepancy between what the Finance team records and what the Inventory team has available, as the latter would not have the historical data necessary for accurate reporting.

Other options could contribute to issues with data processing or delivery, but they do not directly cause a discrepancy in historical sales data as option A does. For example, lacking identifying attributes would impede the ability to ensure operations are idempotent but wouldn’t create discrepancies stemming from different data timelines. Similarly, a misconfigured push endpoint or failure to send acknowledgements would affect message delivery reliability but not create a difference in the sales data recorded between two teams based on missing historical records.