Gene pool can be defined as

Options

A. sum total of genes of all individuals of interbreeding population
B. sum total of genes present in an individual
C. total number of genes of all individuals in a given geographical area
D. total number of genes present among all species in the biosphere

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept of Gene Pool**:
- A gene pool refers to the complete set of genetic information within a population. It encompasses all the alleles (variations of genes) present in the individuals of that population.

2. **Analyzing the Options**:
- **Option A**: "Sum total of genes of all individuals of an interbreeding population."
- This option correctly describes the gene pool as it focuses on a population that interbreeds, which is essential for defining a gene pool.

- **Option B**: "Sum total of genes present in n individuals."
- This option is incorrect because it suggests looking at a specific number of individuals rather than the entire interbreeding population.

- **Option C**: "Total number of genes of all individuals in a given geographical area."
- This option is also incorrect as it does not account for the fact that multiple populations can exist within a geographical area.

- **Option D**: "Total number of genes present among all species in the biosphere."
- This option is incorrect because a gene pool is specific to a population, not the entire biosphere or all species.

3. **Selecting the Correct Answer**:
- After evaluating all the options, **Option A** is the correct definition of a gene pool, as it accurately describes the genetic composition of an interbreeding population.

**Final Answer**: The gene pool can be defined as the sum total of genes of all individuals of an interbreeding population.

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