Which of the following statement is not true with respect to variation ?

Options

A. All variations in a species have equal chance of survival
B. Change in genetic composition results in variation
C. Selection of variants by environmental factors forms the basis of evolutionary processes
D. Variation is minimum in asexual reproduction

Explanation

**Step-by-Step Solution:**

1. **Understanding Variation**: Variation refers to the differences that exist among individuals of the same species. It is essential for the process of natural selection and evolution.

2. **Analyzing the Statements**:
- **Statement 1**: "All variations in species have equal chances of survival."
- This statement is incorrect. In nature, not all variations have equal chances of survival. Only those variations that are advantageous or fit for the environment are more likely to survive and reproduce.

- **Statement 2**: "Change in genetic composition results in variation."
- This statement is true. Variations arise due to changes in the genetic makeup of individuals, which can occur through mutations, genetic recombination, etc.

- **Statement 3**: "The selection of variants by environmental factors forms the basis of the evolutionary process."
- This statement is also true. Natural selection acts on variations, favoring those that are better suited to the environment, which leads to evolutionary changes over time.

- **Statement 4**: "Variation is minimum in asexual reproduction."
- This statement is true as well. Asexual reproduction typically results in offspring that are clones of the parent, leading to minimal variation.

3. **Conclusion**: After analyzing all the statements, the first statement is the only one that is not true with respect to variation. Therefore, the correct answer is **Statement 1**.

---