Concept:First generation computers used vacuum tubes, which made their operation very costly.
Explanation:The question asks which generation of computers had expensive operation costs.
First generation computers (1940s–1950s) relied on thousands of vacuum tubes.
These tubes consumed large amounts of electricity and produced excessive heat.
Special cooling systems were needed to prevent overheating, which raised daily expenses.
They also required frequent maintenance because vacuum tubes burned out quickly.
Additionally, the machines were very large and needed constant technical attention.
Second generation computers used transistors, which were cheaper, smaller, and more reliable.
Third and fourth generations used integrated circuits and microprocessors, further reducing running costs.
Therefore, the highest operational cost belongs to the first generation.
Answer:A. First generation