Answer:
A.
Explanation:
The two excerpts talk mainly about the shortage of fish for the consumption of human population.
In the excerpt Overfishing, the author is talking about the causes of shortage of fish caused due to overfishing. The next excerpt Acquaculture talks that this lack can be subdued with farming of seafood, fishes in specific.
So, the common theme in both the excerpts is meeting the world's supply of fish, whose population is declining due to overfishing.
Therefore, option A is correct.