Instructions (in case of doubt):
(1) In each category, it is possible to independently make as many selections as you want (or none at all). However, you should try to select those boxes that best describe your situation, and you should not select every box that might possibly apply. For example, an algorithm for line segments will necessarily deal with the endpoints of those line segments, i.e. points, or possibily the algorithm also works for points by treating them as a special case of a degenerate line segment. but in this case you should check only the box for line segments, in the category Objects below.)

(2) If your paper contains several results/algorithms you can answer the questions below for that aspect of your paper which is most characteristic, in your feeling. For example, the main new achievement of your algorithm is a logarithmic query time, as opposed to a polynomial preprocessing time.
Alternatively, if your paper has several contributions of equal importance, you can check the union of the boxes that you would check for each contribution individually. (For example, an algorithm dealing with points on a line (1d), and another algorithm which handles points in 4d. You can check two boxes in the first category Dimension.)