Malarial parasite is best obtained from a patient

The correct option is C While temperature is rising sharply
Symptoms of malaria appear in cycles. The time between episodes of fever and other symptoms varies with the specific parasite. Episodes of symptoms may occur, every 48 hours if infected with P. vivax or P. ovale. Every 72 hours, if infected with P. malariae. P. falciparum does not usually cause a regular, cyclic fever. The cyclic pattern of malaria symptoms is due to the life cycle of malaria parasites as they develop, reproduce and are released from the red blood cells and liver cells in the human body. This cycle of symptoms is also one of the major signs that you are infected with malaria.

Therefore, the correct answer is option C.