Find the incorrect statement from the following .

Options

A. Majority of Euglenoids are fresh water organisms found in stagnant water.
B. Slime moulds are saprophytic protists.
C. In diatoms , the cell walls form two thin non - overlapping shells, which fit together as in a soap box.
D. Dinoflagellates are mostly marine and photosynthetic.

Answer

To solve the question of finding the incorrect statement from the given options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: Majority of euglenoids are freshwater organisms and found in stagnant water.**
- **Analysis:** This statement is correct. Euglenoids are primarily found in freshwater environments, particularly in stagnant water bodies. They are known for their adaptability to such conditions.

2. **Statement 2: Slime molds are also members of the Protista kingdom and are saprophytic, growing on dead decaying organic matter.**
- **Analysis:** This statement is also correct. Slime molds belong to the Protista kingdom and are saprophytic organisms, meaning they feed on dead and decaying organic material.

3. **Statement 3: In diatoms, the cell wall forms two non-overlapping shells.**
- **Analysis:** This statement is incorrect. Diatoms have a unique cell wall structure that consists of two overlapping halves, resembling a petri dish or soap box. Therefore, the correct description should state that the shells are overlapping, not non-overlapping.

4. **Statement 4: Dinoflagellates are mostly marine and photosynthetic.**
- **Analysis:** This statement is correct. Dinoflagellates are primarily found in marine environments and many are photosynthetic, contributing significantly to marine food webs.

### Conclusion:
From the analysis, the incorrect statement is **Statement 3**, which incorrectly describes the structure of diatom cell walls as non-overlapping.

### Final Answer:
The incorrect statement is: **In diatoms, the cell wall forms two non-overlapping shells.**

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