The diagram below shows two ways of connecting three bulbs $A, B$ and $C$ to a $220 \,V$ main in a room. Name the two arrangements. Which of them would you prefer for household electricity? Give two reasons.

(D) The arrangement shown in figure $(i)$ is a series arrangement. The arrangement in figure $(ii)$ is a parallel arrangement.
We would prefer the parallel arrangement for household electricity. The reasons are:
$(i)$ In a series arrangement,if one of the bulbs fuses,the circuit breaks and the other bulbs also cease to glow. However,in a parallel arrangement,if one bulb fuses,the other bulbs continue to glow because they are connected in independent branches.
$(ii)$ In a series arrangement,the total resistance of the circuit increases as more bulbs are added,which reduces the current and makes the bulbs glow less brightly. In a parallel arrangement,each bulb receives the full voltage of the source,so the brightness of one bulb remains unaffected when another bulb is switched on or off.