The drawbacks or limitations of two-kingdom classification are

Options

A. eukaryotes and prokaryotes .
B. photosynthetic and non-photosynthetic plants
C. unicellular and multicellular orgenisms .
D. all of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Two-Kingdom Classification:**
- The two-kingdom classification system was proposed by Carl Linnaeus. It divides living organisms into two main kingdoms: Plantae (plants) and Animalia (animals).

2. **Identifying Drawbacks:**
- The two-kingdom classification has several limitations that affect its effectiveness in categorizing all living organisms. Here are the main drawbacks:

3. **Lack of Distinction Between Eukaryotes and Prokaryotes:**
- In this classification, there is no distinction made between eukaryotic organisms (which have a defined nucleus) and prokaryotic organisms (which do not have a defined nucleus). This is a significant limitation as it overlooks the fundamental differences in cellular structure.

4. **Inclusion of Photosynthetic and Non-Photosynthetic Organisms:**
- The classification does not differentiate between photosynthetic plants (like green plants) and non-photosynthetic organisms (like fungi). Both types are placed under the Plantae kingdom, which can lead to confusion regarding their biological functions and characteristics.

5. **Lack of Distinction Between Unicellular and Multicellular Organisms:**
- The two-kingdom system fails to separate unicellular organisms (like bacteria and protozoa) from multicellular organisms (like plants and animals). This lack of distinction can obscure the understanding of the diversity and complexity of life forms.

6. **Conclusion:**
- The drawbacks of the two-kingdom classification system include the lack of distinction between eukaryotes and prokaryotes, the inclusion of both photosynthetic and non-photosynthetic organisms in the same kingdom, and the failure to differentiate between unicellular and multicellular organisms. Therefore, the correct answer to the question is that all of the above are limitations of the two-kingdom classification.

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