Which of the following is a device used for mathematical calculations during exams?

• A. Calculator
• B. Weather Service
• C. Ball Pen
• D. Effective Expression

Answer: (A)

Calculators are tools specifically designed to perform mathematical operations quickly and accurately, which is why they’re used during exams. They handle basic arithmetic and often more advanced functions, helping you compute complex problems faster and with fewer mistakes when permitted. The other options don’t fit as calculation devices: a weather service provides weather information, not a tool for doing math; a ball pen is for writing; and effective expression isn’t a device at all. So the calculator is the best choice for performing mathematical calculations during exams.