`G_1,(S )`and G-2 are sub-phases of ...................

Explanation

**Step-by-Step Solution:**

1. **Identify the Context of the Question:**
The question asks about the phases labeled G1, S, and G2.

2. **Understand the Phases:**
- G1 Phase: This is the first gap phase where the cell grows in size and synthesizes RNA and proteins.
- S Phase: This is the synthesis phase where DNA replication occurs, resulting in the doubling of the DNA content.
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