Explanation:

- A computer performs several core functions which are essential to its operation.

- Option 1: Accept and process data - Fundamental function; computers process and transform input data into usable information.

- Option 2: Store data - Essential function; computers store data for future access and processing.

- Option 3: Scan text - Correct. While a computer can interact with peripherals that scan text, scanning itself is not a basic function performed by the computer's main components.

- Option 4: Accept input - Core function; receiving data from users or devices for processing.