Sulphur shower is due to

Options

A. Acid rain
B. Excess `SO_(2)` and `SO_(3)` in atmosphere
C. Exposed sulphur rocks
D. Pollen of Pinus/Cedrus.

Answer

**Step-by-Step Solution:**

1. **Identify the Source of Sulphur Shower**: The sulphur shower phenomenon is primarily caused by the pollen from certain plants. In this case, the pollen from the genus Pinus (pine trees) is specifically mentioned.

2. **Understand the Structure of Pollen**: The pollen grains of Pinus have two wings on either side. These wings are adaptations that facilitate the dispersal of pollen through the air.

3. **Mechanism of Dispersal**: When the male cones of Pinus are brushed or disturbed, they release a large quantity of pollen into the atmosphere. This release occurs during the pollination season.

4. **Visual Effect**: As the pollen is dispersed by the wind, it can create a visual effect that resembles a yellow cloud or shower, hence the term "sulphur shower." The yellow color comes from the high concentration of pollen grains.

5. **Conclusion**: Therefore, the sulphur shower phenomenon is due to the pollen of Pinus and similar coniferous trees like cedars.

**Final Answer**: The sulphur shower is due to the pollen of Pinus and cedars.

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