Question

Which of these is an alternating current?

• A. b, c, d
• B. only d
• C. All of these
• D. None of these

Answer 1

The correct option is D None of these

Since all the currents have values only above the X-axis, that means they are all in the same direction. Only their magnitude keeps changing. They don't start flowing in the negative direction. In other words, they are all DC.