Each cell shows a shape with some dots inside. Find what stays the same along each row and down each column, then pick the missing cell.

Down each column the shape is the same (triangles, squares, pentagons), and along each row the number of dots is the same (1, 3, 5). The empty cell is in the pentagon column and the 5-dot row, so it is a pentagon with 5 dots: (d). (a) has the dots of the middle row, (b) is a square and (c) has 6 dots.