Answer:
B. Neither country could monitor all of the ports covered by the regulations.
Step-by-step explanation:
This conflict occurred in early 1800s, during the Napoleonic war between two alliances. But French and British empire were considered to be the dominant forces.
At that time, both countries threatened each other that they will block their international trades through sea route.
Historians considered their threats "Paper Blockages" because none of them have enough ships to fully block all the ports. They only gave the threats to appear stronger but they did not possess enough resources to enforce it.
Because of this, their threat of blockade was seen as really weak, as weak as a paper. That's where the name came from.