What is extraction, transformation, and loading?C$1)$ A process of entering data, tracking data, and loading it into a database$\mathrm{.}2)$ A process that extracts data from internal and external databases, transforms it using a common set of enterprise definitions, and loads it into a data warehouse$\mathrm{.}3)$ A process that is performed at the end of the data warehouse model prior to putting the data in a cube$\mathrm{.}4)$ A process that is performed at the beginning of all business processes.