How does a Mode S interrogator identify aircraft?

Question

ATPL - Airline Transport Pilot license - Radio Navigation - How does a Mode S interrogator identify aircraft?

QuizVDS · Accepted Answer

A 24 bit identifier, giving over 16 million combinations

QuizVDS · Answer

An eight bit identifier, which gives 212 unique combinations

QuizVDS · Answer

The P3 pulse

QuizVDS · Answer

Only found above the correct glideslope

ATPL: How does a Mode S interrogator identify aircraft?