In order to calculate the period of the wave, we can use the formula below:
[tex]T=\frac{1}{f}[/tex]
So, to calculate the period, let's use the given frequency of 200 Hz:
[tex]T=\frac{1}{200}=0.005=5\cdot10^{-3}\text{ s}[/tex]
Therefore the correct option is A.
