Choose odd one w.r.t dinoflagellates.

Options

A. mostly fresh water
B. stiff cellulosic plates
C. two different flagella
D. cause red tides

Answer

To solve the question of choosing the odd one with respect to dinoflagellates, we can follow these steps:

### Step 1: Understand the Characteristics of Dinoflagellates
Dinoflagellates are a group of single-celled organisms that belong to the kingdom Protista. They are primarily marine and photosynthetic, possessing unique features such as pigments that give them various colors.

### Step 2: Identify the Key Features of Dinoflagellates
1. **Habitat**: Mostly marine (oceanic environments).
2. **Cell Structure**: They have stiff cellulose plates in their cell wall.
3. **Flagella**: They possess two different types of flagella, one longitudinal and one transverse.
4. **Phenomenon**: They are known for causing red tides, which can be harmful to marine life due to toxin release.

### Step 3: Analyze the Given Options
Now, we need to evaluate the options provided in the question. The odd one out will be the statement that does not align with the characteristics of dinoflagellates.

1. **Mostly Fresh Water**: This statement is incorrect as dinoflagellates are primarily marine organisms.
2. **Stiff Cellulosic Plates**: This is a correct characteristic of dinoflagellates.
3. **Two Different Flagella**: This is also a correct characteristic.
4. **Cause Red Tides**: This is another correct characteristic.

### Step 4: Choose the Odd One Out
From the analysis, the first option, "Mostly Fresh Water," is the odd one out because dinoflagellates are predominantly found in marine environments, not freshwater.

### Final Answer
The odd one with respect to dinoflagellates is **"Mostly Fresh Water."**

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