Four identical resistors are arranged with a battery as illustrated. Each resistor has a resistance of $120\,\Omega$. Resistor $R_4$ is taken out. What effect does the removal of this resistor have on the circuit’s effective resistance?
- AThe effective resistance does not change.
- BThe effective resistance decreases by $20\,\Omega$.
- CThe effective resistance increases by $20\,\Omega$.
- DThe effective resistance decreases by $120\,\Omega$.