challenge: What did Brian Conrey, Bui, and Young prove in 2011 regarding the Riemann zeta function zeros?
  
  A. Exactly 41 percent of the zeros are on the imaginary axis
  B. More than 41 percent of the zeros are on the real line
  C. More than 41 percent of the zeros are at the origin
  D. Less than 41 percent of the zeros are on the critical line
  Answer: 