Which one of the following statement is not true ?

Options

A. Pollen grains of some plants cause servere allergies and bronchies afflications in some people
B. The flowers pollinated by flies and bats secrete foul odour to attract them
C. Honey is made by bees by digesting pollen collected from flowers
D. Pollen grains are rich in nutriens and they are used in the form of tablets and syrups

Explanation

### Step-by-Step Solution:

1. **Read the Question**: The question asks which statement is not true among the given options related to pollen grains and their functions.

2. **Evaluate Each Statement**:
- **Statement A**: "Pollen grain of some plants cause severe allergies and bronchitis in some people."
- This statement is true. Pollen grains can indeed cause allergic reactions, such as hay fever.

- **Statement B**: "The flower which is pollinated by flies and birds secretes foul odor to attract them."
- This statement is also true. Some flowers emit odors to attract pollinators like flies and birds.

- **Statement C**: "Honey is made by bees by digesting pollen collected from the flower."
- This statement is false. Honey is made by bees by digesting nectar, not pollen.

- **Statement D**: "Pollen grains are rich in nutrients and they are used in the form of tablets and syrup. Many athletes use this pollen grain to increase their stamina."
- This statement is true. Pollen grains are indeed rich in nutrients and are used as dietary supplements.

3. **Identify the False Statement**: After evaluating all statements, it is clear that Statement C is not true.

4. **Conclusion**: The statement that is not true is **C**: "Honey is made by bees by digesting pollen collected from the flower."

### Final Answer:
The statement that is not true is **C**.

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