Gonyaulax undergo rapid multiplication that they make the sea appear red. This phenomenon is called as :

Options

A. Red sea
B. Red snow
C. Red tide
D. Red drop

Answer

To answer the question regarding the phenomenon where Gonyaulax undergoes rapid multiplication causing the sea to appear red, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organism**: Recognize that Gonyaulax is a type of dinoflagellate, which is a single-celled organism belonging to the group of protists.

2. **Understand the Multiplication**: Acknowledge that Gonyaulax can undergo rapid multiplication, which is a characteristic behavior of some dinoflagellates.

3. **Recognize the Phenomenon**: When dinoflagellates like Gonyaulax multiply quickly, they can cause a significant change in the color of the water, often resulting in a reddish hue.

4. **Name the Phenomenon**: This specific occurrence is known as "Red Tide." It is a term used to describe the discoloration of seawater caused by the high concentration of these organisms.

5. **Choose the Correct Option**: From the options provided (Red Sea, Red Snow, Red Tide, Red Drop), the correct answer is "Red Tide."

### Final Answer:
The phenomenon where Gonyaulax undergoes rapid multiplication causing the sea to appear red is called **Red Tide**.

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