If the statement 'All trucks are polluting vehicles' is given as false, then which of the following statements can be immediately inferred to be true?

If 'All trucks are polluting vehicles' is false, then 'Some trucks are not polluting vehicles' is true.

The A proposition and the O proposition are contradictories.

Contradictories always carry opposite truth-values.

So the falsity of the universal affirmative guarantees the truth of its O.

This is the immediate inference by contradiction on the square of opposition.