challenge: What is the typical height range of a Hakea ivoryi shrub or small tree?
  
  A. 2 to 12 metres (7 to 39 ft)
  B. 5 to 20 metres (16 to 66 ft)
  C. 1 to 3 metres (3 to 10 ft)
  D. 10 to 30 metres (33 to 98 ft)
  Answer: 