Which of the following figures is the odd one out?

The correct answer is Option (4) → 

Look for a line of symmetry of the whole figure, dots included (a line that divides the figure into two mirror halves). In three figures the two dots lie in a level row, one on each side of the middle, so the whole figure has a line of symmetry. In Option (4) the rhombus itself is symmetric, but its two dots are not in mirror positions, so the whole figure cannot be divided into two mirror halves in any way. It is the odd one out.

Option (1) — Incorrect. A triangle with two dots inside: the dots are mirror images across the upright middle line, so the whole figure has a line of symmetry.

Option (2) — Incorrect. A pentagon with two dots inside: the dots are mirror images across the upright middle line, so the whole figure has a line of symmetry.

Option (3) — Incorrect. An octagon with two dots inside: the dots are mirror images across the upright middle line, so the whole figure has a line of symmetry.