Newcastle disease is caused by? By: Sunday|Published on: Jun 9|Categories: Agricultural Science WAEC| 0 comments A. virus B. bacterium C. protozoan D. fungus Correct Answer: Option A – virus Users Also Read These:A tropical disease caused by Trypanosoma is?Which of the following disease is caused by a bacterium?A disease of rabbit caused by a protozoan is?Which disease is caused by a virus?Streak disease of maize is caused by?SEE ALSO The farm machinery used to sow seeds and apply fertilizer at the same time is?