In a Young's double slit experiment, two slits are illuminated with a light of wavelength $$800$$ nm. The line joining $$A_1P$$ is perpendicular to $$A_1A_2$$ as shown in the figure. If the first minimum is detected at $$P$$, the value of slits separation $$a$$ will be:

The distance of screen from slits $$D = 5$$ cm. Answer in mm.

A

0.4 mm

B

0.5 mm

C

0.2 mm

D

0.1 mm