In a Biology Lab Exercise,you Are Asked to Examine Cells

In a biology lab exercise,you are asked to examine cells of a growing onion root tip,that has been sectioned to show many cells.In most of the cells,you easily see the circular or oval nucleus as a uniformly filled space in a membrane outline.In a small percentage of cells,you see chromosomes as distinct strands just as cell division begins,and as it progresses,because the chromatin

A) becomes more tightly folded, increasing their visible length.
B) becomes less tightly folded, increasing their visible length.
C) becomes less tightly wound, to facilitate cell division.
D) becomes more tightly wound, to protect DNA, and to more easily manage cell division.
E) increases in length, as replication adds DNA sections to the original.