How was the Red River cleared for travel?

Question

a) long steel pipes were used to push the debris into nets

b) large nets were used to scoop the debris out of the river

c) a snag boat was used lot clear the debris from the river

d) a steamboat sailed up and won the river with a steel plate attached to the front of the boat so debris could be pushed out of the way

Answer 1

http://www.penhook.org/red_river_raft.htm