Histone Proteins are synthesized during

Answer: Option C

Histone Proteins are synthesized during the S phase.
The S phase (Synthesis Phase) is the phase of the cell cycle in which DNA is replicated, occurring between the G₁ phase and G₂ phase.
S-phase entry also regulates histone production at the RNA level. Instead of poly adenylated tails, canonical histone transcripts possess a conserved 3 stem-loop motif that selectively binds to Stem Loop Binding Protein (SLBP).
During S-phase, the accumulation of SLBP acts together with NPAT to drastically increase the efficiency of histone production.