Kirchhoff's Laws & Measuring Instruments question from JEE Main 2020 (9 Jan, Shift 1)

Answer: (b)

1. The wire BD makes B and D one node: $1 \parallel 4 = 0.8\ \Omega$, $2 \parallel 3 = 1.2\ \Omega$, total $2\ \Omega$, $I = 10\text{ A}$.
2. $V_{AB} = 8\text{ V}$: $I_{1\Omega} = 8\text{ A}$, $I_{4\Omega} = 2\text{ A}$.
3. $V_{BC} = 12\text{ V}$: $I_{2\Omega} = 6\text{ A}$, $I_{3\Omega} = 4\text{ A}$.
4. At B: $8 = 6 + I_{BD} \Rightarrow I_{BD} = 2\text{ A}$ (B to D)
5. So the answer is (b) 2 A.