Answer:
The answer is: a and h, g and b, f and c, d and e.
Explanation:
When the replication machinery assembles the two forks, two primers are obtained (primer a and primer h). Producing the first two primers near the origin of replication (b and g) slows down a bit because the replication fork must open for strands that have lagged behind.
When the lagging strands are completed, the DNA is exposed to produce the second primers (c and f). When these second primers are completed, the DNA is re-exposed to produce the third primers (d and e). In conclusion, due to the shape of the replication bubble, primers that lag close to the origin of replication occur much earlier than primers that are close to the replication fork.
