Chief pollinators of agricultural crops are

Options

A. butterflies
B. bees
C. moths
D. beetles

Explanation

**Step-by-Step Solution:**

1. **Understanding Pollination**: Pollination is the process where pollen grains are transferred from the anther (male part) of a flower to the stigma (female part) of the same or another flower. This can occur through self-pollination or cross-pollination.

2. **Types of Pollination**:
- **Self-Pollination**: Pollen is transferred within the same flower.
- **Cross-Pollination**: Pollen is transferred from one flower to another flower of a different plant.

3. **Pollinating Agents**: For cross-pollination, various agents are involved. These can be categorized into:
- **Abiotic Agents**: Non-living factors such as wind and water.
- **Biotic Agents**: Living organisms that assist in pollination.

4. **Biotic Pollinators**: Among biotic agents, several organisms can act as pollinators:
- **Bees**: The most common and effective pollinators.
- **Butterflies**: Also contribute to pollination but are less common than bees.
- **Other Insects**: Moths, beetles, and various other insects.
- **Other Animals**: Some reptiles, primates, and tree-dwelling rodents can also act as pollinators.

5. **Chief Pollinators in Agriculture**: In agricultural settings, bees are recognized as the chief pollinators. They are responsible for pollinating approximately 30% of all crop plants, making them crucial for agricultural productivity.

6. **Conclusion**: Therefore, the answer to the question "Chief pollinators of agricultural crops are" is **bees**.

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