Plasmodium falciparum is a protozoan parasite, one of the species that causes malaria in humans. A gametocyte in Plasmodium falciparum is a cell specializing in the transition between the human and the mosquito host. Gametocytes arise from erythrocytic asexual stages.

Gut contents of Anopheles mosquitoes

The gut of Anopheles mosquitoes is an important site for the development and transmission of the malaria parasite, Plasmodium. Different stages of the parasite can be found in the gut of these mosquitoes. Among the given options, the correct answer is option 'B', which is gametocytes. Let's understand why gametocytes are found in the gut of Anopheles mosquitoes in detail.

Gametocytes
- Gametocytes are the sexual stages of the Plasmodium parasite. They are produced by asexual replication of the parasite within the human host.
- When a female Anopheles mosquito takes a blood meal from an infected human, it ingests gametocytes along with the blood.
- Once inside the mosquito's gut, the gametocytes undergo sexual reproduction and differentiate into male and female gametes, which are called microgametes and macrogametes, respectively.
- The microgametes fertilize the macrogametes, forming zygotes.
- The zygotes develop into ookinetes, which penetrate the gut wall and form oocysts on the outer surface of the gut epithelium.

Other stages of the parasite
- Sporozoites: Sporozoites are the infective stage of the Plasmodium parasite. They are formed within the oocysts and are released into the mosquito's body cavity.
- Trophozoites: Trophozoites are the asexual stages of the Plasmodium parasite that develop within the red blood cells of the human host.

Conclusion
In the gut of Anopheles mosquitoes, the stages of the Plasmodium parasite that can be found are gametocytes. These gametocytes are ingested by the mosquito during a blood meal and undergo sexual reproduction to produce zygotes, ookinetes, and eventually oocysts, which are important for the transmission of malaria.

Gametocytes are present in the gut of female anophees because at this stage only the mosquito sucks the blood from human body further fertilisation occurs only in mosquitos gut.