Which statement best explains why the US used the chemical Agent Orange?

to cause evacuation of cities
to destroy the civilian economy
to cause sickness in local populations
to remove crops and heavy vegetation

Did the spanish settlers and missions have a positive effect on world history? why, what did they do that was positive? why was the treaty of paris (1763) good for the world/world history? did the plymouth colony have a positive effect on world history? why, what did they do that was positive?