In the given figure,what do '$z$' and '$b$' represent respectively?

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$ :
Assertion $(A)$ : $Spirulina$ is a microbe that can be used for reducing environmental pollution.
Reason $(R)$ : $Spirulina$ is a rich source of protein,carbohydrates,fats,minerals and vitamins.
In the light of the above statements,choose the most appropriate answer from the options given below:

$A$ - Scientist Alexander Fleming discovered the first antibiotic.
$R$ - Methanogens are used for fermenting malted cereals and fruit juices to produce ethanol.

Match the following columns correctly:

Column $I$	Column $II$ and $III$
$(a)$ Trichoderma	$(s)$ Cyclosporin $A$ - $(iv)$ Immunosuppressive agent
$(b)$ Vitamin	$(q)$ Riboflavin - $(ii)$ Vitamin
$(c)$ Monascus purpureus	$(r)$ Statins - $(iii)$ Blood cholesterol lowering agent
$(d)$ Streptococcus	$(p)$ Streptokinase - $(i)$ Clot buster

Mark the mismatched pair:

Match List-$I$ with List-$II$:

List-$I$	List-$II$
$A$. Clostridium butylicum	$1$. Ethanol
$B$. Saccharomyces cerevisiae	$II$. Streptokinase
$C$. Trichoderma polysporum	$III$. Butyric acid
$D$. Streptococcus sp.	$IV$. Cyclosporin-$A$

Choose the correct answer from the options given below: