The bulb in the tester does not glow when current is passed through

cbse-class-8
science
chemical-effects

#1

The bulb in the tester does not glow when current is passed through it. What can be the possible reasons for this ?
A. The possible reasons for this are :
(a) the connections may be loose.
(b) the bulb may be defective.
© the cells may be defective.