Medel proposed something was being stably passed down unchanged from parents to offspring called
(a) Genes
(b) Genotype
(c) Factors
(d) Alleles

Options

A. Genes
B. Genotype
C. Factors
D. Alleles.

Answer

To solve the question regarding what Mendel proposed was being stably passed down unchanged from parents to offspring, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Mendel's Work**: Gregor Mendel is known as the father of genetics. He conducted experiments on pea plants and observed how traits were inherited from one generation to the next.

2. **Identifying the Key Term**: The question asks for the term Mendel used to describe the units of inheritance that are passed down from parents to offspring.

3. **Analyzing the Options**:
- **(a) Genes**: While this term is widely used today, Mendel did not use this term in his original work.
- **(b) Genotype**: This refers to the genetic makeup of an organism, not the units being passed down.
- **(c) Factors**: Mendel originally referred to the units of inheritance as "factors." This term was later replaced by "genes."
- **(d) Alleles**: These are different forms of a gene, not the term Mendel used for the units of inheritance.

4. **Conclusion**: Based on Mendel's original terminology, the correct answer is (c) Factors, as this was the term he used to describe the hereditary units that were passed down unchanged from parents to offspring.

### Final Answer:
(c) Factors

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