A student, intending to catch a bus, finds that the bus starts and accelerates away with uniform acceleration $$a=2\text{ m s}^{-2}$$ when he is 16 m far from the bus. He runs with unifor$$\mathrm{m\ s^{-1}}$$peed so as just to catch the bus. The minimu$$\mathrm{m\ s^{-1}}$$peed with which the student must run is

A

$$2.0\text{ m s}^{-1}$$

B

$$4.0\text{ m s}^{-1}$$

C

$$8.0\text{ m s}^{-1}$$

D

$$16.0\text{ m s}^{-1}$$