Answer:
Anaphase
Step-by-step explanation:
Before the mitosis process (where cells multiply creating two new daughter cells from a single cell) chromosomes are replicated and remain attached to their replicates, then they are condensed forming microtubules as they align on the metaphase plate. Now the sister chromatids (replicates) begin to separate to the opposite poles due to the action of the spindle in anaphase (You can observe this in the image I added). Then telophase begins when the nuclear envelope forms back again and chromosomes begin to unroll.
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