Which of the following infection$(s)$ can be diagnosed by the use of polymerase chain reaction $(PCR)$?

Consider the given statements and select the true ones $:-$
$(A)$ Health could be defined as a state of complete physical,mental and social well-being.
$(B)$ Pathogens can enter our body by various means,multiply and never interfere with the functions of organs/organ systems.
$(C)$ Salmonella typhi is a pathogenic virus which causes typhoid fever.
$(D)$ Plasmodium reproduces asexually in liver cells and $\text{RBC}$ of human.

Which of the following is a mental disease?

Given below are the pairs of pathogens and the diseases caused by them. Which out of these is not a matching pair and why?
$(a)$ Virus - Common cold
$(b)$ Salmonella - Typhoid
$(c)$ Microsporum - Filariasis
$(d)$ Plasmodium - Malaria

Identify the number of correct statements from the following:
$(1)$ Gene therapy is used in the treatment of $ADA$ deficiency.
$(2)$ Tetanus causes sustained muscle contraction. There is a lack of relaxation phase.
$(3)$ Cigarette smoking leads to asthma in the respiratory system.
$(4)$ $A$ transplanted kidney in a patient can fail due to cell-mediated immunity.
$(5)$ Serum globulin is an antibody.

Match the following columns:

Column-$I$	Column-$II$
$1$. Allergy	$a$. Immunodeficiency
$2$. Autoimmunity	$b$. Serotonin
$3$. $AIDS$	$c$. $IgA$
$4$. Colostrum	$d$. Multiple sclerosis