Which of the following are thick walled resting spores formed under unfavourable condition?

Options

A. Sporangiospore
B. Conidia
C. Chlamydospores
D. Oidia

Answer

To solve the question regarding which spores are thick-walled resting spores formed under unfavorable conditions, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks for the identification of thick-walled resting spores that are formed when conditions are unfavorable for growth.

2. **Identifying Types of Spores**:
- We need to analyze the options provided in the question. The common types of spores include:
- Chlamydospores
- Sporangiospores
- Conidia
- Oidia

3. **Analyzing Each Type of Spore**:
- **Chlamydospores**:
- These are indeed thick-walled resting spores. They are formed under unfavorable conditions and can remain viable until conditions improve, allowing them to germinate.
- **Sporangiospores**:
- These are produced in a sporangium and are typically not thick-walled resting spores. They are involved in asexual reproduction.
- **Conidia**:
- These are asexual spores that are produced by fungi, particularly in the Ascomycetes and Basidiomycetes. They are not typically thick-walled resting spores.
- **Oidium**:
- These are a type of asexual spores that arise from the fragmentation of hyphae. They do not have the characteristics of thick-walled resting spores.

4. **Conclusion**:
- After analyzing the characteristics of each spore type, it is clear that the correct answer is **Chlamydospores**. They are the thick-walled resting spores formed under unfavorable conditions.

### Final Answer:
The correct answer is **Chlamydospores**.

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