Which type of feature can represent both points and lines in vector data?

The correct choice is a feature class. In GIS, a feature class is a collection of similar features stored in a dataset; it can represent different types of geometric shapes such as points, lines, and polygons. This flexibility allows for the management of various spatial data types in a cohesive manner.

Feature classes are fundamental components in a geodatabase that enable users to perform analyses and visualize data effectively. Each feature class can be designed to contain specific kinds of data, which might include points (e.g., locations of schools) or lines (e.g., roads). When defining a feature class, the geometry type can be set according to the intended representation, making it versatile for different applications.

In contrast, a layer file is a reference to a feature class or a raster dataset and does not inherently store features. A feature dataset is a collection of feature classes that share a common spatial reference, but it doesn't directly represent the features itself. A geodatabase is a general term for a database or file system used to store and manage spatial data, which can contain multiple feature classes and datasets, but it does not directly refer to the representation of features like points and lines.