Which of the following statements is correct about $DNA$ polymerase?

Which property of $DNA$ double helix led Watson and Crick to hypothesise semiconservative mode of $DNA$ replication? Explain.

Given below are two statements,one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R).$
Assertion $(A):$ $\text{DNA}$ replication occurs within a small opening of the $\text{DNA}$ helix,referred to as the replication fork.
Reason $(R):$ During transcription,the discontinuously synthesized fragments of $\text{DNA}$ are joined by the enzyme $\text{DNA}$ ligase.
In the light of the above statements,choose the most appropriate answer from the options given below:

In $DNA$ strand replication, Okazaki fragments are:

How many types of $DNA$ polymerases are present in bacteria?

In $DNA$ replication,in which direction does the synthesis of the new strand occur?