Combination of Inductors, LR & LC Circuits question from JEE Main 2002 (AIEEE)

Answer: (d)

1. Label the junctions: $A$, $P$ (after 1st coil), $Q$ (after 2nd coil), $D$.
2. The top wire joins $A$ to $Q$; the bottom wire joins $P$ to $D$. So $Q \equiv A$ and $P \equiv D$.
3. Each 3 H coil now lies between $A$ and $D$: all three are in parallel.
4. $\frac{1}{L} = \frac{1}{3}+\frac{1}{3}+\frac{1}{3} = 1 \Rightarrow L = 1\text{ H}$
5. So the answer is (d) $1\text{ H}$.