Answer:
B. Metaphase
Step-by-step explanation:
Mitosis occurs when the cell replicates the chromosomes and splits to form two daughter cells.
The first and longest phase of mitosis is prophase. During prophase, chromatin condenses into chromosomes, and the nuclear envelope (the membrane surrounding the nucleus) breaks down.
The second phase is metaphase. During metaphase, the nucleus dissolves and the cell's chromosomes condense and move together, aligning in the center of the dividing cell