what best describes the relationship between wavelength and frequency in an electromagnetic wave?\nalways…

what best describes the relationship between wavelength and frequency in an electromagnetic wave?\nalways equal\nno relationship\ndirectly proportional\ninversely proportional
Answer
Brief Explanations:
The speed of an electromagnetic wave ($c$) is constant in a vacuum. The formula relating wavelength ($\lambda$), frequency ($f$) and speed is $c = \lambda f$. Rearranging gives $f=\frac{c}{\lambda}$, showing an inverse - proportion.
Answer:
D. inversely proportional