What does the part labeled '$A$' in the given figure represent?

Select the correct option for the plant shown below.

Identify the molecules $(a)$ and $(b)$ shown below and select the right option giving their source and use:

Assertion $(A):$ In Pneumonia and common cold, close contact with an infected person should be avoided.
Reason $(R):$ Pneumonia and common cold are airborne diseases.

Match the following columns:

Column-$I$	Column-$II$
$1.$ Typhoid	$a.$ Trichophyton
$2.$ Pneumonia	$b.$ Rhinovirus
$3.$ Common cold	$c.$ Haemophilus influenzae
$4.$ Ringworm	$d.$ Salmonella typhi

Identify the molecules $(A)$ and $(B)$ shown below and select the right option giving their source and use.
| Molecule | Source | Uses |
| :--- | :--- | :--- |