The main task of an educational computer is

The main task of an educational computer covers scoring the answers, preserving the information and analysis of data, so all of these apply.

Scoring answers lets the computer evaluate responses quickly and give immediate feedback.

Preserving information means storing records, content and results reliably for later use.

Analysis of data lets it process performance and other figures to inform teaching decisions.

Since the computer performs all three functions, no single option alone captures its role.

These functions underlie both Computer Assisted Instruction and Computer Managed Instruction.