Which of the following figure is odd one among the all.

The correct answer is Option 3: 

Option 1: A square has 4 sides, so the number matches the sides.

Option 2: Circle with a small circle inside. A circle has 0 sides, so the inner circle represents 0, which is consistent with the shape.

Option 3: A triangle has 3 sides, so the number matches the sides.

Option 4: A diamond (square rotated) with 3 inside. But a diamond (square) has 4 sides, not 3.

Conclusion: The number inside should represent the number of sides of the shape, but Option 4 breaks this rule.