Which vehicle has an acceleration of 5 m/s²?
A a bicycle, when its speed changes from rest to 2.5 m/s in 2s
B a car, when its speed changes from rest to 15 m/s in 5s
C a lorry, when its speed changes from rest to 20 m/s in 15s
D a motorbike, when its speed changes from rest to 50 m/s in 10s