The correct option is D 8C
DNA replication occurs during the S phase of interphase due to which the content of DNA gets doubled in the cell.
Interphase has a long duration and is divided into G1, S and G2 phases.
During G1 phase, cells are metabolically active and cellular contents are synthesized and thus there is overall cell growth. G1 phase is followed by S phase. DNA replication occurs in the S phase where DNA synthesis occurs and the content of DNA gets doubled. At the end of G1 phase, each chromosome has one chromatid. But after the S phase, each chromosome will have two chromatids. These two chromatids are identical copies of each other. After S phase, the cell enters into G2 phase and the DNA content remains the same as in S phase. Hence, if the DNA content in G1 phase is 4C, then the DNA content in G2 phase will be 8C. C here refers to the content of DNA.