Which one is incorrect ?

Options

A. Plasmodium falciparum, malaria, relapse, mosquito
B. Trypanosoma gambiense, Glossina Sleeping sickness, Winterbottom signs
C. Wuchereria bancrofti, elephantiasis, microfilariae, mosquito
D. Entamoeba histolytica, dysentery, quadrinucleate cyst, colon.

Answer

To solve the question "Which one is incorrect?", we need to analyze each option provided and determine if the statements about each organism are accurate or not.

### Step-by-Step Solution:

1. **Analyze Option 1: Plasmodium falciparum**
- Plasmodium falciparum is indeed a parasitic protozoan that causes malaria in humans.
- It has two hosts: the female Anopheles mosquito (where sexual reproduction occurs) and humans (where asexual reproduction occurs).
- Other species of Plasmodium, such as Plasmodium ovale and Plasmodium vivax, can enter a dormant stage in the liver, leading to relapsing malaria.
- However, Plasmodium falciparum does not cause relapsing malaria; it is known for being fatal.
- Therefore, the statement regarding Plasmodium falciparum is incorrect.

2. **Analyze Option 2: Trypanosoma gambiense**
- Trypanosoma gambiense is a protozoan that causes sleeping sickness, transmitted by the tsetse fly (Glossina).
- The description of how it infects the body and causes symptoms like swollen lymph nodes (Winterbottom's sign) is accurate.
- Thus, this option is correct.

3. **Analyze Option 3: Wuchereria bancrofti**
- Wuchereria bancrofti is a nematode that causes elephantiasis (filariasis).
- It is transmitted by mosquitoes, specifically the Culex mosquito, and is characterized by the enlargement of limbs.
- The information provided about this organism is correct.

4. **Analyze Option 4: Entamoeba histolytica**
- Entamoeba histolytica is a protozoan that causes amoebic dysentery (amoebiasis).
- The infective stage is the quadranucleate cyst, which is indeed found in the colon.
- This description is also accurate.

### Conclusion:
After analyzing all the options, we find that the incorrect statement is in **Option 1: Plasmodium falciparum**.

### Final Answer:
The incorrect option is **Option 1: Plasmodium falciparum**.

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