A 12V battery is connected to three resistors as follows: R1=6Ω is in series with a parallel combination of R2=3Ω and R3=2Ω. Let IR1,IR2 and IR3 denote the currents through R1,R2 and R3 respectively. Which of the following correctly ranks these currents in decreasing order?
(a) IR3>IR2>IR1
(b) IR1>IR2=IR3
(c) IR1>IR3>IR2
(d) IR3>IR1>IR2