Combination of Resistors question from JEE Main 2022 (26 Jun, Shift 2)

Answer: (c)

1. Reduce from the far left: the two $5\ \Omega$ in series $= 10\ \Omega$, parallel with the $10\ \Omega$ to A gives $5\ \Omega$.
2. Next $5\ \Omega$ in series gives $10$, parallel with the next $10\ \Omega$ to A gives $5\ \Omega$ again. The same happens at every step.
3. Last step: $5 + 5 = 10\ \Omega$ in parallel with the $10\ \Omega$ from A to B $= 5\ \Omega$.
4. So the answer is (c) $5\ \Omega$.