How does mode S system differ from mode A and C?

A)
Uses pulse technology
B)
More data can be transferred
C)
Extension of secondary radar
D)
One way travel of radio signal

Correct Answer :   More data can be transferred


Explanation : The mode S system works similar to that of mode A and mode C system and causes a transponder to reply when its identity is not known. In a mode S system, additional data other than just altitude and identity can be provided in the MTI.