Genotype is .

Options

A. Genetic composition of species
B. Genetic composition of plastids
C. Genetic composition of germ cells
D. Genetic composition of an individual

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Genotype":**
- Genotype refers to the genetic constitution of an organism. It is the specific set of genes that an individual possesses.

2. **Analyzing the Options:**
- a) Genetic composition of species: This refers to the overall genetic makeup of a species, not an individual.
- b) Genetic composition of plastids: Plastids are organelles in plant cells, and their genetic makeup does not define the organism's genotype.
- c) Genetic composition of germ cells: Germ cells are involved in reproduction, but the term "genotype" specifically refers to the genetic makeup of an individual organism.
- d) Genetic composition of an individual: This option directly defines genotype as it pertains to the specific genetic makeup of one individual.

3. **Conclusion:**
- The correct answer is option D, as it accurately describes what a genotype is.

**Final Answer:**
Genotype is the genetic composition of an individual (Option D).

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