The correct answer is: C. equal to 0.707 times the peak amplitude.
The root mean square (rms) value of a sine wave is the square root of the average of the squared values of the wave over one cycle. It is equal to 0.707 times the peak amplitude.
Option A is incorrect because the number of cycles completed in one second is called the frequency.
Option B is incorrect because the time required to complete one full cycle is called the period.
Option D is incorrect because the peak amplitude is the maximum value of the sine wave.
Option E is incorrect because the rms value of a sine wave is not equal to 1.41 times the peak amplitude.