Concept:A modern computer operates using three core functional units for processing data.
Explanation:The basic functional units are the input unit, the processor (CPU), and the output unit.
The input unit accepts data and instructions.
The processor performs calculations and controls operations.
The output unit delivers the processed results to the user.
Storage and memory support these functions but are not counted among the three primary functional units.
FOTRAN, COBOL, and black box are programming languages or unrelated terms.
Answer:A. input, processor and output units