A Punnett square can help in obtaining:

Options

A. Genotypes
B. Phenotypes
C. Genotypic and Phenotypic ratios
D. All of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Punnett Square**: The Punnett square is a diagram that is used in genetics to predict the outcome of a particular cross or breeding experiment. It is named after the geneticist Reginald C. Punnett.

2. **Purpose of the Punnett Square**: The primary purpose of the Punnett square is to determine the possible genotypes of offspring from a genetic cross. It helps in visualizing how alleles from the parents combine.

3. **Genotypes and Phenotypes**:
- **Genotype** refers to the genetic makeup of an organism (e.g., AA, Aa, aa).
- **Phenotype** refers to the observable traits or characteristics of an organism (e.g., flower color, height).

4. **Genotypic and Phenotypic Ratios**: The Punnett square also allows us to calculate the ratios of different genotypes and phenotypes that can result from the genetic cross.
- **Genotypic ratio** is the ratio of different genotypes produced (e.g., 1:2:1 for a monohybrid cross).
- **Phenotypic ratio** is the ratio of different phenotypes produced (e.g., 3:1 for a monohybrid cross).

5. **Conclusion**: Since the Punnett square can help in obtaining genotypes, phenotypes, and their respective ratios, the correct answer to the question is "all of these".

**Final Answer**: D) All of these.

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