The power and wavelength emitted by a laser pointer commonly used in Power Point presentations are 1.0 mW and 670 nm respectively. Number of photons emitted by this pointer during a presentation of 5 minutes is

A

$$1.01 \times 10^9$$

B

$$1.01 \times 10^{21}$$

C

$$1.6 \times 10^{16}$$

D

$$1.01 \times 10^{18}$$