Answer:
"Air" is the correct solution.
Step-by-step explanation:
- A mode of carriage whereby the flight attendants, mail as well as cargo were often transported by air. This technique's biggest advantages seem to be the substantial duration of information saved owing to the increased flying speed.
- It is indeed a network whereby local airports provide air transport to something like a centralized airport whereby long-haul flights become accessible.
So that the above seems to be the right approach.