Two resistances R1 and R2 give combined resistance of 4.5 ohms when in series and 1 ohm when in parallel. The resistances are
(A) 3 ohms and 6 ohms
(B) 3 ohms and 9 ohms
(C) 1.5 ohms and 3 ohms
(D) 1.5 ohms and 0.5 ohms
