Which OmniScript element can retrieve data from multiple sources?

The Integration Procedure Action is the correct choice because it is specifically designed to retrieve data from multiple sources and aggregate that data, allowing for complex data manipulations and transformations before presenting it to the user. This action can call various endpoints, including those from external systems and Salesforce, enabling it to gather data from multiple locations in a single operation.

This functionality is crucial in scenarios where applications require data from different systems to provide a holistic view or a comprehensive set of information. For instance, in a customer service application, an integration procedure could pull data concerning a customer from both Salesforce objects and an external database, consolidating it into a single response for further processing.

In contrast, other choices, while useful for specific tasks, have defined scopes. The Calculation Action focuses on performing computations rather than retrieving data, the DataRaptor Extract Action is intended to extract data specifically from Salesforce objects via defined mappings but does not aggregate from multiple heterogeneous sources, and the Matrix Action is typically used for structuring or displaying data rather than retrieving it. Thus, the Integration Procedure Action stands out as the optimal choice for gathering information from diverse origins.