The inability of seed to germinate in the absence of favourable external conditions is called as

Options

A. quiescence
B. viability
C. bolting
D. dormancy

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the inability of seeds to germinate when favorable external conditions are absent. This means we need to identify a term that describes this specific condition.

2. **Analyzing the Options**:
- **Option 1: Quiescence**: This term refers to a state where seeds do not germinate due to unfavorable external conditions, such as lack of water or appropriate temperature. However, they can germinate once favorable conditions return.
- **Option 2: Viability**: This term refers to the ability of seeds to germinate when conditions are suitable. It does not specifically address the inability to germinate due to unfavorable conditions.
- **Option 3: Bolting**: This term describes the premature flowering of plants before they are harvested and is not related to seed germination.
- **Option 4: Dormancy**: This term refers to a state where seeds do not germinate even when favorable conditions are present. It is a different concept than what the question is asking.

3. **Identifying the Correct Answer**: Since the question specifically refers to the inability of seeds to germinate in the absence of favorable conditions, the correct term is **quiescence**. This is because quiescence describes a temporary state of rest that can be resolved once conditions improve.

4. **Final Answer**: The inability of seed to germinate in the absence of favorable external conditions is called **quiescence**.

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