Several seeds respond best when

Options

A. the daily temperature is high
B. the daily temperature is low
C. the daily temperature alternates between high and low.
D. the daily pressure alternates between high and low

Answer

**Step-by-Step Solution:**

1. **Understanding Seed Germination Requirements**: Seeds require specific conditions to germinate effectively. The primary factors include water, oxygen, and temperature.

2. **Evaluating Temperature Options**:
- **Option A**: Daily temperature is high. This is incorrect because excessively high temperatures can hinder seed germination.
- **Option B**: Daily temperature is low. This is also incorrect since very low temperatures can prevent seeds from germinating effectively.

3. **Considering Alternating Temperatures**:
- **Option C**: Daily temperature alternates between high and low. This option is correct as seeds often respond best to a range of temperatures that can stimulate growth and germination.

4. **Assessing Pressure**:
- **Option D**: Daily pressure alternates between high and low. This is incorrect because atmospheric pressure does not significantly affect seed germination.

5. **Conclusion**: Based on the analysis, the best condition for seed response is when the daily temperature alternates between high and low.

**Final Answer**: The correct option is C: the daily temperature alternates between high and low.

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