What is the part of the cell cycle process by which chromosomes in a cell nucleus are separated into two identical sets of chromosomes

Mitotic phase

Explanation:

Cell cycle is composed of interphase and mitotic phase. Interphase is aphase of cell preparation. It is subdivided into:

G1 (gap 1 phase)-the cell grows and becomes largerS phase- replication of DNA, duplication of centrosomesG2 (gap 2 phase)-proteins and oranelles are made

Mitotic phase is phase of cell division, chromosomes are separated, daughter cell get identical sets of chromosomes. It is followed by cytokinesis-separation of cytoplasm. Stages of mitosis are:

prophase-condensation of chromatin into chromosomes,  the nuclear envelope breaks down, mitotic spindle formationmetaphase-the chromosmes line up (metaphase plate)anaphase-the siste chromatides move toward opposite cell polestelophase-the nuclear envelope forms again, cell division is almost complete

The answer to this is b