Question

chromosomes are duplicated during.
a the g1 phase.
b mitosis.
c cytokinesis.
d the g2 phase.
e the s phase.

Explanation:

The cell - cycle has different phases. In the S (synthesis) phase, DNA replication occurs, which leads to the duplication of chromosomes. In G1, the cell grows and prepares for DNA synthesis. Mitosis is the process of nuclear division. Cytokinesis is the division of the cytoplasm. G2 is a phase for further cell growth and preparation for mitosis.

Answer:

E. the S phase