Match the following columns:

Column $I$	Column $II$
$A$. Recombinant $DNA$	$1$. Sea weeds
$B$. Gel electrophoresis	$2$. $DNA$ staining
$C$. Ethidium bromide	$3$. Plasmid $DNA$ that has incorporated human $DNA$
$D$. Agarose	$4$. Process by which $DNA$ fragments are separated based on their size

Assertion : In recombinant $DNA$ technology,human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote).
Reason : Both bacteria and yeast multiply very fast to form huge population,which express the desired gene.

Read the following statements carefully and select the correct option $:-$
$(A)$ Source of the restriction enzyme Hind $II$ is Haemophilus influenzae.
$(B)$ If any protein encoding gene is expressed in a heterologous host,it is called as recombinant protein.
$(C)$ Microinjection method for injecting foreign gene is used for animal cell.
$(D)$ $\text{DNA}$ primers are chemically synthesized oligonucleotides that are complementary to the regions of $\text{DNA}$ in $\text{PCR}$.
How many of the above statements are correct?

Match the organism with its use in biotechnology:

$(a)$ Bacillus thuringiensis	$(i)$ Cloning vector
$(b)$ Thermus aquaticus	$(ii)$ Construction of first rDNA molecule
$(c)$ Agrobacterium tumefaciens	$(iii)$ $DNA$ polymerase
$(d)$ Salmonella typhimurium	$(iv)$ Cry proteins

$(a)\quad (b)\quad (c)\quad (d)$

What do '$S$' and '$T$' represent in the given figure of a stirred-tank bioreactor?

What do '$X$' and '$Y$' represent in the given figure of a stirred-tank bioreactor?