Area & Pythagorean Theorem – Lecture 13 (Geometry)

Why does the lecture treat the three starting facts about area as postulates rather than proving them?

1. A.They are false in non-Euclidean geometries.
2. B.Their proofs require the concept of a limit, which belongs to calculus.
3. C.They follow trivially from the parallel postulate.
4. D.They depend on the axiom of choice.