The correct option is A A→Q , B→P , C→R , D→Q
In series :
Current passing through resistors connected in series will remain same , where as potential drop across the resistor depends on the value of resistance.
In parallel :
Potential difference across the resistors remains same where as the current distributes in the inverse ratio of resistances.
Let R be the effective resistance and I be the total current in the circuit.
Current passing through 2Ω resistor , I2=IR4R2+R4=4I6=2I3
Current passing through 4Ω resistor , I4=IR2R2+R4=2I6=I3
Current passing through 3Ω resistor , I3=IR5R3+R5=5I8
Current passing through 5Ω resistor , I5=IR3R3+R5=3I8
Therefore, I4<I5<I3<I2 .......(1)
So, A→Q and B→P
Power generated across 2Ω resistor is , P2=I22R2=8I29
Power generated across 4Ω resistor is , P4=I24R4=4I29
Power generated across 3Ω resistor is , P3=I23R3=75I264
Power generated across 5Ω resistor is , P5=I25R5=45I264
Therefore, P3>P5>P2>P4 ....(2)
So, C→R and D→Q
Hence, option (a) is the correct answer.