Final answer:
An extract is a snapshot of the data that Tableau stores locally, which is good for very large datasets or when only a few fields are needed.
Step-by-step explanation:
The correct answer is 1) Extract. An extract in Tableau is a snapshot of the data that Tableau stores locally. It is a compressed and optimized version of the data that allows for faster performance when working with very large datasets or when only a few fields are needed. By extracting and storing the data locally, Tableau avoids repeatedly accessing the original data source, resulting in faster queries and visualizations.