Solubility product of silver bromide is $$5.0 \times 10^{-13}$$. The quantity of potassium bromide (molar mass taken as $$120$$ g mol$$^{-1}$$) to be added to $$1$$ litre of $$0.05$$ M solution of silver nitrate to start the precipitation of AgBr is

A

$$1.2 \times 10^{-10}$$ g

B

$$1.2 \times 10^{-9}$$ g

C

$$6.2 \times 10^{-5}$$ g

D

$$5.0 \times 10^{-8}$$ g