Which of the following drugs produce depression of the central nervous system?

Arsenic drugs are mainly used in the treatment of

$4-$hydroxyacetanilide belongs to which of the following?

Which of the following types of drugs reduce body temperature?

The correct match between items of List-$I$ and List-$II$ is

List-$I$	List-$II$
$A$. Phenelzine	$p$. Pyrimidine
$B$. Chloroxylenol	$q$. Furan
$C$. Uracil	$r$. Hydrazine
$D$. Ranitidine	$s$. Phenol

Which of the following statements are correct?
$(i)$ Drugs that mimic natural messenger by switching on the receptor are called agonists.
$(ii)$ Shape of the receptor does not change after attachment of chemical messenger.
$(iii)$ $A$ cationic detergent is formed when stearic acid reacts with polyethylene glycol.
$(iv)$ Seldane is an antihistamine.