Why does x is None distinguish None reliably from other falsy values such as 0 and an empty list?
None is a singleton, so identity singles it out.✓Правильный ответ
Every falsy value is another spelling of None.
x == False and x is None always mean the same thing.
Identity converts every falsy value to None.
Объяснение
None has a single shared identity, so the test asks specifically whether x refers to that singleton. General falsiness is broader: zero and an empty list are falsy but are different objects and meanings.