The following are requirement of seeds for germination to occur :

Options

A. oxygen for increased metabolism
B. adequate temperature
C. adequate water
D. all of the above

Explanation

To answer the question regarding the requirements for seed germination, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Seed Germination**:
- Seed germination is the process through which a seed develops into a new plant. This involves the activation of the seed's metabolic machinery.

2. **Requirement of Oxygen**:
- Oxygen is essential for increased metabolism. During germination, the seed embryo requires oxygen to carry out cellular respiration, which provides the energy necessary for growth and development.

3. **Importance of Adequate Temperature**:
- Adequate temperature is crucial for seed germination. Each seed species has an optimal temperature range for germination. If the temperature is too low or too high, it can inhibit the germination process.

4. **Role of Adequate Water**:
- Water is vital for germination as it helps to hydrate the seed, activating enzymes that initiate the growth process. Water also facilitates the transport of nutrients within the seed.

5. **Conclusion**:
- All three factors—oxygen, adequate temperature, and adequate water—are necessary for successful seed germination. Therefore, the correct answer is "all of the above."

### Final Answer:
The requirements for seeds to germinate are oxygen for increased metabolism, adequate temperature, and adequate water. Thus, the correct option is "all of the above."

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