Question

Ok, this may seem to most an irrelevant question, concerning logic, but I don't have the strongest sense of logic. So may someone aid in directing me toward the correct form of logic in this question? It goes like this:
Look at the statement below.

“All squares are quadrilateral.”

Which of these is a logically equivalent statement?

If it is not a square, it is not a quadrilateral.

All quadrilaterals are squares.

If it is not a quadrilateral, it is not a square.

It will be a quadrilateral if and only if it is square.

Answer 1

C is true :)

Answer 2

Ok, thanks!

Answer 3

your welcome :)