What type of announcement can be made using a PushTopic in Salesforce?

Using a PushTopic in Salesforce is specifically designed for real-time notifications based on changes to records in Salesforce. PushTopics utilize the Salesforce Streaming API, enabling external applications or clients to subscribe to a particular channel and receive updates when certain changes occur in Salesforce data.

In this context, case closure alerts align perfectly with the functionality of a PushTopic. When a case is closed within Salesforce, the relevant record change can trigger a notification, which is effectively communicated to any subscribed clients. This allows for immediate awareness and response to significant changes, which is essential in environments focused on customer support and case management.

The other choices, while they represent important types of announcements, don't fit as neatly with the intended use of PushTopics. Internal team updates might not pertain directly to record changes in Salesforce, price change notifications may not necessarily trigger updates based on Salesforce record changes, and system maintenance notifications generally involve proactive communications rather than reactive notifications tied directly to record updates. Thus, case closure alerts stand out as the most appropriate use case for announcing updates through a PushTopic.