Step 1: Understanding the Properties of a Square.
A square is a special type of rectangle where all four sides are of equal length. This is one of its defining properties.
Step 2: Verifying the Options.
- Option (1): All sides of a square are equal, making this the correct answer.
- Option (2): This is incorrect as all sides of a square are equal.
- Option (3): Opposite sides are equal in a rectangle, not a square.
- Option (4): The ratio of sides in a square is 1:1, not 1:2:3:4.
Conclusion:
Therefore, the correct answer is (1) All sides are equal.