Which row gives the correct definitions of a wave's frequency and speed?
- 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