Many events are periodic. The seasons and the calendar are periodic. If you have a music lesson every Tuesday after school, it is a periodic event. Which statement best explains why the table of elements is periodic?
A. It has many different parts, each of which is different from other parts.
B. All elements are included in the table.
C. It has rows and columns, as a calendar does.
D. Properties of the elements repeat in a cycle or repeating pattern.