The analogy presented is comparing a car's typical storage space, which is a garage, to the storage space for an airplane. Just as a garage is where you park a car, a hanger is where airplanes are stored and maintained. Here's a brief description of each option:

• Runway: This is a pathway for takeoff and landing, not for storage.
• Hanger: This is a building where airplanes are kept when they're not in use, making it the correct choice.
• Terminal: This is a facility where passengers board and disembark airplanes, not a storage space.
• Sky: This refers to the airspace above the ground, not a physical space for storage.

Thus, the correct answer is "Hanger" because it directly parallels the relationship of a car to its garage.