Capacitors $$C_1=3\,\mu\text{F}$$, $$C_2=6\,\mu\text{F}$$, $$C_3=4\,\mu\text{F}$$ and $$C_4=1\,\mu\text{F}$$ are connected in a circuit as shown to a battery of $$60\,\text{V}$$. Now if key K is closed, the charge that will flow through K is

A

$$90\,\mu\text{C}$$ from b to a

B

$$60\,\mu\text{C}$$ from b to a

C

$$30\,\mu\text{C}$$ from a to b

D

$$150\,\mu\text{C}$$ from b to a