challenge: What was Derek Blake's position at Oriel College, Oxford until 2007?
  
  A. Research Assistant in Biomedical Sciences
  B. Professor of Biomedical Sciences
  C. Isobel Laing Post-Doctoral Fellow in Biomedical Sciences and Wellcome Trust Senior Fellow in Basic Biomedical Science
  D. Wellcome Trust Junior Fellow in Basic Biomedical Science
  Answer: 