The frequency of a mutant gene in a population is expected to increase, if the gene is

Options

A. dominant
B. recessive
C. sex linked
D. favourable selected

Answer

To solve the question regarding the frequency of a mutant gene in a population, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Mutant Genes**: A mutant gene is a variant of a gene that has undergone a mutation. Mutations can lead to changes in traits that may affect an organism's fitness in its environment.

2. **Role of Natural Selection**: Natural selection is a process where organisms with traits that confer a survival advantage are more likely to reproduce and pass those traits on to the next generation. This means that if a mutant gene provides an advantage (increased fitness), it is more likely to be passed on.

3. **Favorable Selection**: If a mutant gene is beneficial (favorable), it will increase the chances of survival and reproduction for individuals carrying that gene. Over generations, this leads to an increase in the frequency of that mutant gene in the population.

4. **Contrasting Other Factors**: The question mentions other factors like dominance, recessiveness, and sex-linkage. While these factors can influence how traits are expressed, they do not directly determine whether the frequency of a mutant gene will increase. The key factor is whether the gene is favorably selected.

5. **Conclusion**: Therefore, the frequency of a mutant gene in a population is expected to increase if the gene is favorably selected.

### Final Answer:
The frequency of a mutant gene in a population is expected to increase if the gene is **favorably selected**.

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