What Effect Did the Union Naval Blockade of Southern Ports

What effect did the Union naval blockade of southern ports have on the Confederacy?

A) Much to the surprise of the North, it did not have much effect, since most foreign imports were still coming into the South.
B) It quickly choked off southern commercial activity, including the flow of goods and military weapons to and from Europe.
C) It inspired dramatic southern economic growth since the South was forced to become self-sufficient.
D) It succeeded in terms of harming coastal cities, but the Mississippi River had so few tributaries that other trade routes were not in danger.
E) It prompted Britain to offer diplomatic recognition to the Confederacy because it was so afraid of potential economic repercussions.