
Answer:
 P_a = 3P₀ ,  P_b = 2 P₀ ,    P_c = 3 P₀
P_c> P_b> P_a
Explanation:
To determine which circuit consumes more energy than is given by the expression
      P = V I
      V = I R
      I = V / R
      P = V² / R
As all circuits have the same battery, the value of the resistance to which the battery is connected determines the consumption
Circuit A
In this circuit the three bulbs are in series so the total resistance is
     R_total = 3 R
the power dissipated is
     P_a = V² / 3R
if we call
     P₀ = V² / R
   Â
we substitute
     P_a = P₀/3
Circuit B
Two bulbs are connected in series
      R_total = 2 R
power is
    P_b = V2 / 2R
    P_b =  P₀/2
Circuit C
The 3 bulbs are connected, but in parallel, the resistance is
    1 / R_totak = 1 / R + 1 / R + 1 / R
    R_total = R / 3
    P _c = V2 3 / R
    P_c = 3 Po
By reviewing these results, we can sort the circuits
    P_c> P_b> P_a