The existence within a population of non-beneficial alleles in heterozygous genotype is :-

Options

A. genetic load
B. genetic drift
C. genetic flow
D. selection

Answer

To answer the question regarding the existence within a population of non-beneficial alleles in heterozygous genotype, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- First, we need to understand what is meant by "non-beneficial alleles" and "heterozygous genotype." Non-beneficial alleles are those that do not provide any advantage to the organism, and a heterozygous genotype refers to having two different alleles for a particular gene.

2. **Identifying the Options**:
- The options provided are genetic load, genetic drift, genetic flow, and selection. We need to analyze each option to see which one fits the description given in the question.

3. **Analyzing Genetic Load**:
- Genetic load refers to the presence of non-beneficial alleles in a population. It is defined as the reduction in the average fitness of a population compared to a population that consists entirely of individuals with optimal genotypes. This concept directly relates to the existence of non-beneficial alleles in heterozygous individuals.

4. **Considering Genetic Drift**:
- Genetic drift is the random change in allele frequencies in a population over time. While it can lead to the loss of beneficial alleles, it does not specifically refer to the presence of non-beneficial alleles.

5. **Considering Genetic Flow**:
- Genetic flow (or gene flow) involves the transfer of genetic material between populations through migration and interbreeding. This process does not inherently relate to the presence of non-beneficial alleles.

6. **Considering Selection**:
- Selection is the process by which certain traits become more common in a population due to their advantages. It typically works against non-beneficial alleles, rather than describing their existence.

7. **Conclusion**:
- Based on the analysis, the correct answer to the question is **genetic load**, as it specifically addresses the existence of non-beneficial alleles in heterozygous genotypes.

### Final Answer:
The existence within a population of non-beneficial alleles in heterozygous genotype is known as **genetic load**.

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