Who discovered the malarial parasite?

'Black water fever' is a very serious complication of

Which protozoan is found as a commensal in the human colon?

In the life cycle of $Plasmodium$,where does the exo-erythrocytic cycle occur?

Assertion $A$: $Plasmodium$ is a microscopic protozoan.
Reason $R$: Humans and female $Anopheles$ mosquitoes are the hosts of $Plasmodium$.
Which option is correct for Assertion $A$ and Reason $R$?

If all ponds and puddles are destroyed,the organism likely to be destroyed is