Chromosomes are formed during which phase of cell cycle
Though the DNA is synthesized during the S phase of cell cycle, but the condensation of chromatin fibers into Chromosomes happens during metaphase of Mitosis phase (M) of cell cycle. Hence, if question ask about which phase of cell cycle for DNA synthesis, the answer is S phase. If asked about the chromosome formation, answer is M phase.
G1
S
G2
M
Replication