Answer
Mitosis.
Two individual identical sister chromatids can be seen between prophase, when the DNA condenses, and anaphase, when the sister chromatids are pulled apart.
Work Step by Step
During S or Synthesis phase, the DNA duplicates. During G2 nothing happens to the DNA. The DNA starts to condense during Prophase, the first step of mitosis. The DNA starts to become less condensed during Telophase.