$A$ person suffering from a disease caused by $Plasmodium$ experiences recurring chill and fever at the time when:

• A
  the sporozoites released from $RBCs$ are being rapidly killed and broken down inside the spleen.
• B
  the trophozoites reach maximum growth and give out certain toxins.
• C
  the parasite after its rapid multiplication inside $RBCs$ ruptures them,releasing the stage to enter fresh $RBCs$.
• D
  the microgametocytes and megagametocytes are being destroyed by the $WBCs$.