The period of a wave will bed 2 second. Frequency is the inverse of the time period;Option A is correct.
Frequency is defined as the number of repetitions of a wave occurring waves in 1 second.
Frequency is given by the formula as,
[tex]\rm f = \frac{1}{t} \\\\ t= \frac{1}{f} \\\\ t= \frac{1}{0.5} \\\\ t= 2\ second[/tex]
The period of a wave will be 2 second.
Hence, option A is correct.
To learn more about the frequency, refer to the link;
https://brainly.com/question/14926605
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