Question

6.
Consider the circuit below :
[INJSO STAGE-2 2009-10]
(A) If the bulb A burns out, then bulb C stays lighted, bulb B burns brightly l
(B) If the bulb B burns out, then bulb C goes off and D stays lighted
(C) If the bulb C burns out, bulb A and B go off
(D) If the bulb D burns out, the event is unnoticeable, and bulbs A, B, C stays lighted.
OD
E​

Answer 1

Explanation:

D opt. is correct, as A, B and C already form a closed circuit and will remain unaffected by D.