The protein that helps in opening the $DNA$ double helix at the replication fork is .......... .

Match the following columns:

Column-$I$ (Enzyme)	Column-$II$ (Function)
$P$. $DNA$ Polymerase	$I$. Synthesizes $DNA$ strand
$Q$. $DNA$ Helicase	$II$. Breaks $H$-bonds of $DNA$ strands
$R$. $DNA$ Ligase	$III$. Joins $DNA$ fragments

During the replication of a bacterial chromosome,$DNA$ synthesis starts at the origin of replication and proceeds in:

$DNA$ polymerase links nucleotides by forming which type of bond?

For proving the semi-conservative mode of replication of $DNA$,$E. coli$ were first grown in a medium containing?

Given below are two statements.
Statement $I$ - The template strand with free $3'$ end is called leading template and the strand with free $5'$ end is called lagging template.
Statement $II$ - Replication always starts at the $3'$ end of the template strand and proceeds towards the $5'$ end of the template.
In the light of the above statements,select the correct option given below: