State True or False
(i) Chromosomal aberrations are commonly observed in cancer cells
(ii) Mutation is the only phenomenon that leads to variation in DNA.

Explanation

**Step-by-Step Solution:**

1. **Evaluate Statement (i):** "Chromosomal aberrations are commonly observed in cancer cells."
- Chromosomal aberrations refer to changes in the structure or number of chromosomes. Research has shown that cancer cells often exhibit these aberrations due to genetic mutations and environmental factors. These changes can lead to uncontrolled cell growth, which is characteristic of cancer.
- **Conclusion for (i):** This statement is **True**.

2. **Evaluate Statement (ii):** "Mutation is the only phenomenon that leads to variation in DNA."
- A mutation is defined as a sudden change in the DNA sequence. While mutations do contribute to genetic variation, they are not the only source. Other processes, such as meiosis and crossing over, also create genetic diversity by recombining genetic material. This means that variations can occur through mechanisms other than just mutations.
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