The diagram depicts a sketch of a wave pattern over a brief time interval. Which statement correctly describes this wave?
- AThe wave is longitudinal, has a wavelength of $20\,\text{cm}$ and is stationary.
- BThe wave is transverse, has a wavelength of $20\,\text{cm}$ and is stationary.
- CThe wave is transverse, has a wavelength of $40\,\text{cm}$ and is progressive.
- DThe wave is transverse, has a wavelength of $40\,\text{cm}$ and is stationary.