Which row correctly gives the frequency and the speed of a wave?
- Afrequency: number of waves; speed: distance travelled per unit time
- Bfrequency: number of waves; speed: time taken for one complete wave to pass a point
- Cfrequency: number of waves passing per unit time; speed: distance travelled per unit time
- Dfrequency: number of waves passing per unit time; speed: time taken for one complete wave to pass a point