Final answer:
The leading strand is synthesized in the same direction as the movement of the replication fork, while the lagging strand is synthesized in the opposite direction. The leading strand is synthesized continuously, whereas the lagging strand is synthesized in short fragments that are ultimately stitched together, the given statement is a. true because these fragments are later stitched together.
Step-by-step explanation:
The leading strand is synthesized continuously, whereas the lagging strand is synthesized in short fragments called Okazaki fragments. These fragments are later stitched together. One reason for this is that DNA polymerase can only add nucleotides in the 5' to 3' direction.
So, the leading strand, which is complementary to the 3' to 5' parental DNA strand, can be synthesized continuously towards the replication fork because the polymerase can add nucleotides in this direction. On the other hand, the lagging strand, which is complementary to the 5' to 3' parental DNA, is extended away from the replication fork in small fragments known as Okazaki fragments, each requiring a primer to start the synthesis.
Overall the given statement is a. true, the process of DNA replication involves simultaneous synthesis of the leading and lagging strands by a single dimeric DNA polymerase-III. The leading strand is synthesized continuously in the same direction as the replication fork, while the lagging strand is synthesized discontinuously in short fragments that are ultimately stitched together.