The expected answers were:

An astable multivibrator

 

 

 

 

 

 Two applications of an astable multivibrator

Counters, Timers
The question was on oscillators, multivibrators and logic gates. Few candidates attempted this question. The performance was not encouraging as reported.
The few candidates who attempted this question failed to draw correctly the circuit diagram of a BJT-based astable multivibrator circuit and state two of its several applications.