The stage of Plasmodium that contains rhoptries is

Options

A. Ookinete
B. Signet ring stage
C. Merozoite
D. Sporozoite.

Explanation

To determine the stage of Plasmodium that contains rhoptries, we can follow these steps:

### Step 1: Understand what rhoptries are.
Rhoptries are specialized secretory organelles found in certain protozoan parasites, including Plasmodium. They are club-shaped and play a significant role in the parasite's ability to invade host cells.

### Step 2: Identify the stages of Plasmodium.
Plasmodium has several life cycle stages:
- **Sporozoite**: The infective stage that is transmitted to humans through mosquito bites.
- **Merozoite**: The stage that emerges from the liver and infects red blood cells.
- **Signet ring stage**: A developmental stage of the parasite within red blood cells.
- **Eukaryote**: This is not a specific stage of Plasmodium but a broader classification of organisms.

### Step 3: Determine where rhoptries are present.
Rhoptries are specifically present in the **Sporozoite** stage of Plasmodium. This is the stage where the parasite is most infectious and is equipped with the necessary organelles to invade host cells effectively.

### Step 4: Eliminate incorrect options.
- **Eukaryote**: Not a specific stage of Plasmodium.
- **Signet ring stage**: While this is a stage of the parasite, it does not contain rhoptries.
- **Merozoite**: This stage does not contain rhoptries either.

### Conclusion:
The correct answer is **Sporozoite**, as it is the stage of Plasmodium that contains rhoptries.

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