In waterlogged soil, plants generally are killed because of

Options

A. Deficiency of minerals
B. Excessive absorption of water
C. The absence of air in the soil
D. Starvation

Explanation

**Step-by-Step Solution:**

1. **Understanding Waterlogged Soil**: Waterlogged soil occurs when the soil is saturated with water, leading to a lack of air spaces in the soil. This condition can happen due to excessive rainfall or poor drainage.

*Hint: Consider what happens to soil when it is overly saturated with water.*

2. **Role of Oxygen in Plant Survival**: Plants require oxygen for respiration, which is essential for their growth and energy production. The roots of the plants take up oxygen from the soil air spaces.

*Hint: Think about how plants obtain oxygen and what happens if that source is cut off.*

3. **Impact of Waterlogging on Oxygen Availability**: In waterlogged conditions, the air spaces in the soil are filled with water, which displaces the air (and thus oxygen). This leads to insufficient oxygen availability for the roots.

*Hint: Reflect on the relationship between water and air in the soil.*

4. **Consequences of Oxygen Deficiency**: Without adequate oxygen, plant roots cannot perform respiration effectively. This can lead to root damage, reduced growth, and ultimately, plant death.

*Hint: Consider what processes are affected when oxygen is not available to the roots.*

5. **Identifying the Correct Answer**: Among the options provided, the absence of air in the soil is the primary reason why plants are killed in waterlogged conditions. Therefore, the correct answer is the absence of air in the soil.

*Hint: Look for the option that directly relates to the lack of oxygen due to water saturation.*

**Final Answer**: In waterlogged soil, plants generally are killed because of the absence of air in the soil.

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