In the life cycle of plasmodium, the gametocyte  develop in :

RBC of human host.

The correct answer is Option (2) –RBC of human host.

Plasmodium is the protozoan parasite that causes malaria. The life cycle of Plasmodium involves two hosts: the mosquito vector and the human host. The asexual stage of the parasite occurs in the human host's liver and red blood cells, while the sexual stage occurs in the mosquito vector's gut.

During the asexual stage of the parasite, Plasmodium replicates asexually within the human host's red blood cells, causing symptoms of malaria. However, during this stage, some parasites differentiate into sexual forms called gametocytes. These gametocytes are taken up by a mosquito when it feeds on the infected human's blood.

Once inside the mosquito, the gametocytes of Plasmodium undergo sexual reproduction to form male and female gametes, which then fuse to form a zygote. The zygote develops into an ookinete, which penetrates the mosquito's midgut wall and forms an oocyst. The oocyst undergoes meiosis to form sporozoites, which migrate to the salivary glands of the mosquito. When the mosquito feeds on a new human host, the sporozoites are injected into the bloodstream, and the cycle begins anew.