Concept:Aluminium alloys are chosen for aircraft because of their favourable physical and chemical properties.
Explanation:Aircraft materials must be strong enough for flight but also as light as possible to reduce fuel consumption.
Aluminium has a low density, so it provides a high strength-to-weight ratio.
It also forms a thin oxide layer that protects it from corrosion, which is vital in harsh atmospheric conditions at high altitudes.
Other metals like steel are stronger but much heavier, making them less efficient for airframes.
Being amphoteric or allotropic does not directly determine its suitability for aircraft construction.
High density and being a non-conductor are disadvantages, while being hard and brittle would make it unsuitable for structural use.
Answer:B. is light and very resistant to corrosion