To some extent viability of pollen grains depends on :-

Options

A. Temperature
B. Humidity
C. Both (1) and (2)
D. Light

Answer

**Step-by-Step Solution:**

1. **Understanding Pollen Grains:**
- Pollen grains are the male gametes in flowering plants (angiosperms). They play a crucial role in sexual reproduction by delivering male gametes to the ovule.

2. **Defining Viability of Pollen Grains:**
- The viability of pollen grains refers to their ability to remain functional and capable of fertilizing the ovule. This is essential for successful reproduction.

3. **Factors Affecting Viability:**
- The viability of pollen grains is influenced by several environmental factors. The two primary factors discussed are:
- **Temperature:** The temperature at which pollen grains are stored or exposed can significantly affect their viability. Extreme temperatures can reduce their lifespan and functionality.
- **Humidity:** The moisture level in the environment also plays a critical role. High humidity can help maintain the viability of pollen grains, while low humidity can lead to desiccation and loss of function.

4. **Evaluating Options:**
- Given the options:
- Option 1: Temperature
- Option 2: Humidity
- Option 3: Both Temperature and Humidity
- Option 4: Light
- Since both temperature and humidity are important for the viability of pollen grains, option 3 (Both Temperature and Humidity) is the correct answer.

5. **Conclusion:**
- The viability of pollen grains depends on both temperature and humidity, making option 3 the most appropriate choice.