Mule is a hybrid, which of the following statements is correct?

Options

A. a) Mule is not a species
B. b) Mule is a new species
C. c) Horse and ass are two populations
D. d) Mule represents a common ancestor of horse and ass

Answer

### Step-by-Step Solution:

1. **Understanding the Term "Hybrid":**
- A hybrid is defined as the offspring resulting from the crossbreeding of two different species. In this case, we are looking at the mule, which is a hybrid.

2. **Identifying the Parent Species:**
- The mule is specifically produced by the mating of a male donkey (Equus asinus) and a female horse (Equus ferus caballus). This crossbreeding is an example of interspecific hybridization, where two species from the same genus are involved.

3. **Characteristics of Mules:**
- Mules are known to be sterile, meaning they cannot reproduce. This sterility arises because of the differing number of chromosomes in horses and donkeys, which leads to complications during reproduction.

4. **Evaluating the Options:**
- The question provides several statements regarding mules. We need to analyze each one to determine its correctness:
- **Option 1:** "Mule is not a species." - This is correct because mules are hybrids and do not constitute a separate species.
- **Option 2:** "Mule is a new species." - This is incorrect; mules are hybrids and not a new species.
- **Option 3:** "Mule represents a common ancestor of horse and ass." - This is also incorrect; mules are offspring, not ancestors.
- **Option 4:** "Mule is a sterile hybrid." - This is correct and aligns with the definition of mules.

5. **Conclusion:**
- The correct statement regarding mules is that they are not a species but a sterile hybrid resulting from the mating of a male donkey and a female horse.

### Final Answer:
The correct statement is: **Mule is a sterile hybrid of a male donkey and a female horse.**

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