Read the following text and answer the following questions on the basis of the same:
A typical anther is bilobed. It is a tetragonal structure consisting of four microsporangia. These microsporangia form pollen sac which on maturity gets filled with a pollen grains. Pollen grains represent the male gametophytes, their cell wall is very hard. Pollen grains of many species cause severe allergies which cause various diseases in human beings.
Study of pollen grains is called ...........

Options

A. Bryology
B. Mycology
C. Algology
D. Palynology

Explanation

**Step-by-Step Solution:**

1. **Understanding the Text**: The text describes the structure and function of an anther, specifically mentioning that it is bilobed and consists of microsporangia that form pollen sacs filled with pollen grains. It also notes the significance of pollen grains as male gametophytes and mentions their role in causing allergies.

2. **Identifying the Key Term**: The question specifically asks for the term that describes the study of pollen grains.

3. **Analyzing the Options**: The options provided in the question likely include terms related to the study of different biological entities. We need to identify which of these terms refers to the study of pollen grains.

4. **Recalling Relevant Knowledge**: The term for the study of pollen grains is known as "palynology." This can be broken down into "palyno," which refers to pollen, and "logy," which means the study of.

5. **Eliminating Incorrect Options**:
- **Bryology**: The study of bryophytes (mosses and liverworts) - Incorrect.
- **Mycology**: The study of fungi - Incorrect.
- **Algology**: The study of algae - Incorrect.
- **Palynology**: The study of pollen grains - Correct.

6. **Conclusion**: The correct answer to the question is "palynology."

**Final Answer**: The study of pollen grains is called **palynology**.

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