challenge: What was the outcome of the Citrus tristeza virus outbreak at the University of California Citrus Experiment Station during Leon Dexter Batchelor's directorship?
  
  A. Around 1000 trees were destroyed to contain the outbreak
  B. Around 9000 trees (87% of the station's orchards) were destroyed to contain the outbreak
  C. The virus was eradicated without any significant loss of trees
  D. The station's orchards were unaffected by the virus
  Answer: 