Read the following statements
$a.$ Heroin, commonly called smack, is obtained by acetylation of morphine.
$b.$ Cocaine is obtained from the latex of Papaver somniferum.
$c.$ Dopamine is excitatory neurotransmitter.
$d.$ Morphine is an effective sedative and pain killer.
Mark the option which includes both correct statement

The secondary host of malaria parasite is

Some diseases are transmitted through contaminated articles. The method is called

People suffering from mental diseases in India number

Acid in stomach, saliva in the mouth, tears from eyes, all prevent microbial growth belong to which of the following barrier?