Answer:
The correct answer is D) None of the above choices are correct.
Step-by-step explanation:
We know that the object completes 100 vibrations in 5 seconds.
The period (T) is the time in which an object or a particle realizes a complete vibration (oscillation).
The period is the inverse of the frequency.
The unit of the period are the seconds.
The period can be calculated using the following equation :

In this exercise :


Therefore, the correct answer is D)